Compost: It Just May Be All You Need

In a previous post I discussed some research findings that suggest a healthy application of compost may be all you really need for your plants to thrive. I reviewed in another post on how I make compost, and several different methods to achieve results of rich “black gold.” In yet another series of posts (starting here) I reviewed my thoughts on growing soil. You might say, I am a believer in healthy soil.

So then, what actually is compost?  Ideally compost is a dark, crumbly material that smells “earthy” that is decomposed organic materials such as leaves, grass, plant matter, manures, etc. In all actuality, composting happens naturally around us and we may not even realize it or take the time to appreciate it. The next time you are taking a hike in the woods, venture off the path and pick up a handful of the “black gold” and see what I mean. It will be earthy smelling, dark and crumbly, as well as a fantastic resource for plants.  What you have just picked up is decades worth of fallen leaves and plant matter that has decomposed with nothing but mother nature to keep an eye on it. Depending on how you make your compost it should have most, if not all, of the macro and micronutrients that you garden will need for a healthy growing season.

So why do we make compost?

Besides the obvious benefit to our gardens there are “fringe benefits” as well of using and making your own compost.

1. Composting reduces the amount of landfill waste. Almost 60% of our municipal waste (13% yard waste, 12% food waste, 34% paper) can be composted and therefore be doing good work in our gardens as opposed to piling up in our landfills.

2. Composting will save you money (as opposed to buying organic inputs) while improving soil tilth, aeration, water holding capacity and returning much needed nutrients.

3. Compost can suppress some soil born disease by out competing the pathogens and adding beneficial microbes.

4. Quite frankly, its just fun to make!

What are the basic considerations when making compost.

This question can be answered in a variety of ways, as it can be as difficult or as complicated as we want to make it. By now, you should know, that I prefer the K.I.S.S. (KEEP IT SUPER SIMPLE) method in just about anything I do. The only materials you really need, at the bare minimal input levels are carbon and nitrogen sources, water, and air. Sure a fork to turn it with, and some fancy barrels to roll it in are nice, but honestly you really only need three things.

Carbon sources (Browns):  Fall leaves, corn stalks, straw*, paper, wood chips/sawdust.

Nitrogen sources (Greens): Vegetable waste, grass clippings, cow manure, horse manure, poultry manure, coffee grounds.

An ideal carbon to nitrogen ratio (C:N) is 30:1. This number is not crucial, but know that too much nitrogen will make it cook hotter, and too little will slow down the process. Do not be confused by the green and brown terms regarding carbon/nitrogen ingredients. Just because something is brown does not automatically render it a carbon source, this is a general statement as there are exceptions:

1. Coffee grounds are an excellent source of nitrogen (and calcium) for the compost pile even though it is brown.

2. Grass, while green, is an excellent nitrogen source, but when it dries to brown, becomes a carbon source.  It is actually recommended to leave your grass clippings on the lawn as they will supply roughly 50% of the feeding for you lawn for the year. The same concerns that I mentioned below regarding straw, should be a consideration for grass as well. Unless you are sure the source of grass is chemical free, it should not be used. Many community composting sites have outlawed the use of grass clippings for this very reason.

3. More on manures in a few minutes.

4. I prefer to use most, if not all, of my kitchen waste in a vermicompost system. This will be covered in another post in detail, but if you do not utilize worm composting for castings, I would highly encourage any gardener to consider it.

5. I think I have covered fall leaves ad nauseum, so no need to be specific here other than use them as much, compost, vermicompost base and whenever you can.

Water.

Water should be added periodically to your compost pile on an as needed basis, and more importantly in the beginning when creating your pile. Rain may not be adequate to fulfill the hydration needs of a compost pile, 40%-60% moisture. To gauge water content of compost, take a handful of it and squeeze it into your fist. If there is no water leakage, it is likely too dry.  If it drips more than a few drops it is too wet.

Air/Temperature

Air and temperature are typically regulated by similar methods, so I have decided to combine them here.  Proper compost turning should give adequate airflow to the pile to create an aerobic process. If your compost pile is slimy or smells foul, it has likely gone anaerobic (lack of air) and could be in trouble. Turn it, turn it, turn it! Anaerobic composting has a high likelihood of growing pathogens as opposed to beneficial microbes and can cause serious health concerns.

You will know when your compost pile needs turned when the internal temperature cools below 140 (60 degrees Celsius) degrees Fahrenheit. At minimum, your pile should be turned at least monthly until finished, if you want compost in a reasonable time period. Ideally your pile should “cook” between 140 – 160 degrees Fahrenheit, that’s 60-71 degrees Celsius for our metric friends in the east, um….and north, well actually in the south too. OK for 98% of the world!  Your compost pile may safely reach as high as 180 degrees Fahrenheit a few days after turning, but should fall to cooking levels within a few days.  Composting temperatures reaching 160 degrees F. should be adequate to kill pathogens as well as weed seeds, anything above a sustained 160 degrees F. risks killing beneficial microbes as well.

If you do not have a compost thermometer it is suggested to dig into the pile and feel the internal temperature. If it is too hot to keep your hand in for more than a few seconds, it should be adequate. The pile should steam when creating any opening or turning.  A small fee of $25 -$50 will save you the trouble of hand testing, as you can find a reasonable compost thermometer on Amazon.

There are a few other items that are required of a good compost pile that you do have some control over.

Time.

Just about any compost pile of any particular C:N ratio will cook in 1-2 years without any work (turning, watering, etc.). Obviously most people do not want to wait that long, therefore turning it can speed up the process and finish in as little as 2-3 months in ideal conditions. Depending on the crop utilization for your compost, it is recommended that a pile sit/cook for a minimum of 6 months if coming in direct contact with the actual fruit or root crops, especially if utilizing manures in your compost pile.

Microbes.

Microbes are likely the single most important component of composting, however you should have little input regarding this. Scattering a few scoops, or shovels of finished compost into you new mix, should get you started with an adequate microbial count.  “Compost activators,” in my opinion, are a waste of time and money. They are mostly nitrogen with some microbes, but do little to gain any significant advantage in your compost pile compared to the cost.  Most research suggests negligible or no advantage in using these products when compared to a few shovels of compost or garden soil.

Size & Outside Temperature.

The size of your compost pile is important. A compost pile larger than 3’x3’x3′ (Thats 1m x 1m x 1m for the other 98%) will be adequate for cooking. Any smaller than this and you will likely have trouble gaining enough thermal mass to reach desired cooking temperatures, resulting in a longer cook. A proper compost pile can be ready in 6 months if cooking over the winter, that same pile can process in half the time during warmer months, especially over the summer.  Outside temperatures play a major factor in composting times, but they are not critical.

What should you not compost?

It is generally advisable to stay away from composting any manure from humans, cats, or dogs (any carnivore really) as the gut flora of these animals increase the likelihood of contaminating your pile with pathogens, even with perfect composting technique and influences. I will not say that this cannot be done safely, as it can be, but you better know EXACTLY what you are doing in these methods as the margin of error is significantly higher. It is my opinion that the risk does not outweigh the benefit in this type of composting, just don’t do it.

 Other products such as milk, dairy, meats, oils, lards, and grease are not advisable to compost. These products do not hold the same pathogen risk as carnivore manure, but they tend to attract rodents and scavengers to your pile, looking for a quick and easy meal (think compost smorgasbord) and can easily destroy a pile looking for an easy snack.

Obviously adding anything treated with herbicides or pesticides is not advisable as these products do not “cook off”, even though some references suggest that they will. If there is any question regarding the viability of your compost, take a cup full and plant a few peas in it or other easy to grow seeds. If the plant sprouts, then dies off, you may have an issue with an herbicide.

*It is becoming more apparent that straw, of any type, is becoming contaminated. Herbicidal products, such as Round-Up (glyphosate) has finally found its way into the product and even with the best composting techniques, may still be present in finished compost. I had been listening to a composting lecture Barbara Pleasant gave at a Mother Earth News conference a few years ago when she discussed these “preliminary findings.” I have since read several articles and spoke to a few people that have had significant failures in their plants that were attributed to herbicides being present in their compost piles due to glyphosate contaminated straw. It is highly recommended that unless you are absolutely positive of a clean source of straw, that you do not use it.

In a nutshell, gather some carbon and nitrogen sources, make a pile in the garden in the fall, and it should be ready by spring planting if you are remotely close. That’s how I do it….

http://nsgl.gso.uri.edu/vsgcp/vsgcpw01002/vsgcpw01002_part9.pdf

Quintuple Composting

This summer I had been watching one of my favorite YouTube sites (J & J Acres) and it really made me think about my evolution in garden composting. In his video ( J & J Hot Compost ) Jared shows how he has built a compost pile using techniques adapted from a Berkeley study and will turn his pile into compost in 18 days. I have composed in almost every way imaginable, but I have never turned anything into compost in 18 days, I’m really interested in seeing how this works out for him.

My methods of composting:

(1) Good Old Fashion Compost Pile. I typically start this in the fall when I “harvest” any plant matter remaining in the garden from dead or dying crops. I also add some grass clippings for the nitrogen value as well as a load or two of chicken manure. I rarely collect grass clippings because the true benefit is leaving them lay to return to the soil and feed your lawn. If you do not have access to animal manures, I don’t think saving a couple weeks of grass clippings as a nitrogen source will hurt anything.

The real workhorse though in this pile is the shredded leaves that I gather and add. It is my opinion that leaf compost is the single greatest thing you can add to your garden, well maybe in a close tie with vermicompost. The products of this compost pile typically go into my raised beds.

(2) Vermicompost. I started vermicomposting a few years ago and wish I would have started even before that. This is by far the easiest method of composting that I do, and offers some of the greatest benefits. I typically use this compost for houseplants and for my favorite plant, my dwarf orange tree. I recently invested in a few additional pounds of worms with the intent of having enough worm casting by spring of next year to make my own seed starting mix of 25% vermicompost, 50% coir, and 25% vermiculite. Should be interesting, if anything, the kids like playing with the worms.

I’m going to rethink my vermicompost methods this winter though, I have seen quite a few guys create habitats outside and do quite well. I have also used 5 gallon buckets, stacking them up three high, and have been successful as well.

(3) Compost Tumbler. This is a relatively new endeavor for me.  Admittedly I have been either too cheap or too busy in the past to buy or build one. I certainly appreciate the ease and results of these devices and was very lucky that I picked one up on craigslist for $60. As soon as I got it, I filled it with kitchen scraps and yard waste and started spinning it. The material has definitely broken down, but I think the weather is just too cold now to see the real benefits. It sits on a frame and is exposed to the elements (wind) during these cold winter nights, which really puts the half nelson on the heat production needed to adequately compost materials. Think of the “Bridge freezes before road” concept. I’m not sure what I will use this compost for, maybe to supplement anything that needs it not otherwise covered by my other composting methods.

(4) Manure Piles. In the past I have always tilled in manure with the fall cleanup that way it is ready for spring planting. I am running out of time this year but my plan is to place large manure piles right in the middle of my gardens and let them compost over winter. In the spring I will then till it in prior to planting. I decided to place these piles in the garden to get the benefit of any leachate being deposited in my garden and not the spot where I compost. Since this compost will be heavy with nitrogen, I’ll reserve it for the heavy feeders like corn, potatoes and melons.

(5) Green Manure.  Almost forgot about this one. Technically I guess this is composting, but its a stretch. Cover crops that I have planted in the fall and summer will be tilled in and add a multitude of organic material and nitrogen fixation to the garden beds. Buckwheat, clover, vetch and winter wheat are my favorites.

Has anyone ever used one of these compost bins?  Let me ask this question another way…Has anyone ever used one of these bins successfully? I have been adding to this compost bin for more than two years. I finally emptied it the other day and was extremely disappointed in the result. I found cornstalks in the bottom that I threw in 2 years ago, still intact with minimal breakdown. Basically all I use this for now is a reservoir for my food scraps until I can move them to a proper compost bin.

Even with all of these methods, I still never seem to have enough compost when I want it. I guess I know what I need to do…..more worms, another tumbler, and bigger piles!!

My Favorite Soil Amendment: Leaf Compost

By now most of the leaves have fallen and everyone is scrambling to get them raked up for the season so that they can get them to the curb for the township to pick them up. I have been busy the last few weeks trying to beat the municipality to the prize.

I do not live “in town” so I have the luxury of not feeling the pressures and headaches of having to get reported to the HOA, to get my fall clean up completed. I just sit back and wait for everyone else to do it! I don’t have many deciduous trees on my property, but this is slowly changing, so my leaf raking is at a minimum. Unfortunately this means I have to depend on others for my fall leaves, and have earned the nickname “Leaf Thief” by a certain Sheriff’s Deputy that I know.

Recently, I got my trailer ready and was out the door at 5 am to score some leaves. I was able to pick up 65 bags in the trailer and another 10 in the truck bed. The next morning I started out at 4 am and was able to score 60+ bags in the trailer and another 10 in the bed. I wish I had more time, because I left at least three times that many at the curb simply because I needed to get to work.

Why do I get up so early to collect leaves you ask? Its simple, but really there are two separate answers here. It is my opinion that the best composts are comprised mostly of #1 worm castings, #2 leaf mulch and #3 animal manures. I use all three and still never seem to have enough. I also add any yard and garden waste to the above, see my previous post (Quintuple Composting ) for more details.

The second part of the answer is that I try to collect these leaves before the traffic rush in the morning because I don’t want to get run over by someone texting, drinking their coffee and trying to change their radio channel while driving 20 mph over the speed limit in an attempt to get to work three minutes quicker, and still be five minutes late. I can be out the door and back home before anyone wakes up leaving enough time to get showered and ready for work/church, etc. This leaves me plenty of time to to whatever with the family after work.

Over the last few years I have perfected my technique in processing fall leaves. Gone are the days of my wife and I raking and lifting, bagging and turning. I can process 50 – 60 bags of leaves in about 45 minutes, by myself. Here is how I do it:

Originally I would dump out 10 bags or so, walk through them to spread them out. I would chop them up with my mower and gather them with my yard rake, then dump them in my composing piles.

My leaf composting has evolved over the years as I would lose a fair amount by mowing over them. I’m not sure where they went though, they must be with that sock I always lose in the dryer. 

These days, I chop them up in a brush mulcher I picked up on Craigslist for $200. This thing is fantastic, it saves me a half day at least.

I just lift up the dump bed, the bags slide down and I process them through. I keep everything in a line instead of in large pile as it is easier to turn with the loader. This pile will end up being about 8 feet wide and 25 feet long.

This is one area near my barn where I have most of my raised beds. The opening of this pile is just wide enough to fit the loader bucket in to turn and eventually remove it for use. I’ll add a few loads of nitrogen source, in the form of animal manures, to each pile and let it cook.

I have this pile cooking in one of the in ground beds. I like to compost this on site, because I don’t lose anything to drainage, it all goes right into the garden. I’ll alternate this site every year among a few of the larger beds I have to “spread the wealth” so to speak. I ended up processing around 370 bags of leaves this year, at 10 lbs a bag (roughly) that’s almost 4,000 lbs of leaf mulch! I even went so far as to approximate how many leaves were involved, 3.8 million!

Just think in a few years, I will have perfected this process even more, when I can sit back and watch my boy have all the fun!

Growing Soil (Part 6)

Cover crops

A general overview of cover crops would suggest that they serve multiple functions in protecting and improving garden soils. Cover crops are an excellent adjunct to compost and manures, and are even more important when these resources are not available or in limited supply. Cover crops, AKA green manures, limit soil erosion, especially over the winter months, add organic material, improve soil tilth and ease compacting, as well as add valuable nutrients.

Cover crops are generally a small grain species that are planted in late summer or mid to late fall (oats, rye, wheat, legumes) depending on your USDA zone. They can and should also be planted anytime a bed will be unplanted with crop for an extended period of time. The important thing to remember is that cover crops that are intended to go dormant, should have enough time to germinate and start some growth before the first hard frost. Cover crops that are killed by frost (buckwheat) need time to have substantial growth to maximize their effect before the frost kill. Generally speaking I like to use buckwheat and white clover that are planted in the spring to cover and optimize bare soil.

Cover crops work via their deep root systems, pulling up nutrients from deep soil that may otherwise not be available to garden plants or leach out of the soil through erosion.  Legumes (clover, vetch, alfalfa), to name a few, are most important in nitrogen fixation. As you can see in the images below, atmospheric nitrogen is captured by the legume plant and stored as nodules in the plan root to be made available during a time of need, in our case, to be tilled under and serve as a nitrogen reservoir for future crops in the garden. Cover crops are an important part of your long term soil management whether you are planting into the ground or in raised beds, the theory and applications are the same.

Common cover crops and their usefulness:

Alfalfa: (Legume)  Sow 1/2 oz. per 100 sq feet in the spring or late summer.  Turn under in the fall or spring. (The real alfalfa)

Barley: Sow 4 oz.. per 100 sq. feet in the spring or late summer/fall.  Turn over in the spring.

Buckwheat: Sow 2 1/2 oz. per 100 sq. feet in the spring or summer and turn over in the fall. This is by far one of my favorite cover crops as it is fantastic for soil tilth. It must be turned before seed heads develop (roughly 4-6 weeks or so) or it will reseed and can become a weed. It will die off quickly with the first threat of frost.

Cowpea (Legume): Sow 4 oz. per 100 sq. feet in the early to late summer for for turnover when it starts to flower. An inoculate will increase effectiveness. Winter kills.

Crimson Clover or White Dutch Clover: (Legume) Sow 3 oz. per 100 sq. feet in the spring or late summer/fall for a fall or spring turnover. Crimson clover is beautiful when it blooms in the spring.

Forage Radish (Tillage radish): Sow 4 oz. per 100 sq. feet in the late summer or fall, at least 3 weeks before the first frost. It will usually kill with three nights in the teens. May be turned under in the spring, but grown in heavier rates, the deep tap root can “self till” the soil. They have a large white taproot that digs deep into soil and rots over the winter/spring. The above soil vegetation that is left can be planted around in the spring for a living (now dead) mulch.

Spring Oats:  Sow 4 oz. per 100 sq. feet in the spring or late summer/early fall for a summer or spring turn. Will winter kill and usually tolerate a low soil pH.

Winter Rye: Sow 4 oz. per 100 sq. feet in the late summer or fall. Turn over in the spring. It is very winter hardy and in my zone 6b can be planted through late September.

Hairy Vetch: (Legume).  Sow 3 oz. per 100 sq. feet in the late summer or fall for a spring turn. Should be inoculated with the appropriate Rhizobium for optimal growth. Should be tilled under at bloom to prevent from becoming a weed problem.

Winter Wheat: Sow 4 oz. per 100 sq. feet in the late summer or fall for a spring turnover. It can be planted later than most cover crops if needed as it is very winter hardy.

A few more “tips” when cover cropping and what do I do?

1. Soil must be prepared as you would for planting crops. Scattered seed must make soil contact in order to germinate and has best germination rates when lightly raked in.

2. Mulch can be pulled back to plant around vegetables and should not interfere with vegetable growth.

3. The clover family makes a fantastic living mulch for vegetable crops and will not negatively affect the intended crop.

4. I try to time the cover crop planting a day (or less) before a good rain. This will help set the seed as well as give it a head start in the growth cycle, otherwise it may sit there ungerminated until the next rain, leaving it susceptible to birds and other critters. (Especially my chickens).

5. Try to combine legumes and non legumes when possible, this combination makes a really nice mix and a noticeable improvement in your soil.

6. What do I do?

a. I love buckwheat for a short cover or planted in the fall to rot for spring planting. It is super easy to pull/process and really improves soil tilth. If I want to save seed for next sowing, the seed heads are very easy to process and save. If you do not want to save seed and/or eliminate the threat of  any reseeding, cut it down after blooming and the first seed heads appear.

b. Clovers are my legume of choice as they are easy to find in my area at a reasonable price. I would prefer Crimson over White Dutch, simply for the red blooms in the spring, but I’ll take what I can get. One other word about the clovers, do not get impatient by their late germination. For whatever reason, I tend to get frustrated by this in the spring, and when I am ready to give up and start over, BOOM, the clover almost appears overnight. It will germinate like clockwork, but we all know what happens when you watch a clock. Tick…..tock…

c. I have also used winter rye in the past, especially when I am late to setting the fall cover crop as it has the latest plant date of the non legumes and is winter hardy.

d. My general mix in the fall is buckwheat, winter rye and a clover species, sometimes white and red.

e. I have tried hairy vetch in the past and it can be complicated. There is an extra step (with some added expense) in the inoculate, and the plants themselves can be a bear to hand process in the raised beds. Tilling; no issue. My understanding is that the vetch sp. fix a significant amount of nitrogen though, so if this is an issue for you, you may want to explore this option.

f. Forage radish:  I am becoming increasingly curious about this product. It is too late for me to experiment with this for the 2016 season, but it is on my radar for next fall. I think I will try this in a test bed to see how it handles over the winter and see just how much tilling I can eliminate. Diakon radish is the species that I have found to be best grown in my area (6b) and readily available at a reasonable price.

For a little different perspective on cover cropping see this excellent Mother Earth Article.

So that’s all she wrote on this series of Growing Soil, well not really. I’m sure I missed something or will realize that I want to cover something in a little more detail later, but that will give me an opportunity for a few supplemental postings.  Stay tuned……

 

 

Sources other than embedded into links in the blog body:

Pennsylvania State Extension

http://pss.uvm.edu/ppp/pubs/oh34.htm

The Maryland Master Gardener Handbook

The Self-Sufficient Life and How to Live It (Seymour)

The Vegetable Gardeners Bible (Smith)

The Truth about Garden Remedies (Gilman)

What’s Wrong With My Vegetable Garden? (Deardorff & Wadsworth)

What’s Wrong With My Fruit Garden? (Deardorff & Wadsworth)

https://www.ghorganics.com/page32.html

http://www.cias.wisc.edu/wp-content/uploads/2008/07/soilorgmtr.pdf

http://balkanecologyproject.blogspot.com/2014/05/nitrogen-fixing-plants.html

http://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_022940.pdf

http://www.motherearthnews.com/organic-gardening/cover-crops-improve-soil-zmaz09onzraw.aspx

Growing Soil (Part 5)

Micronutrients

Micronutrients (trace elements) are identified nutrients essential for plant life and health, but are found in significantly less supply than the macronutrients. Micronutrient deficiencies are more common than you may think, and are often associated with pH abnormalities.

I have found a very good resource  discussing NPK, as well as the micronutrients, defeciency symptoms and some basic definitions and functions.  However, it is a little out of date naming sodium as a micronutrient as well as omitting nickel and vanadium.

Rather than reinvent the wheel, I have summarized a few of the key components of this website below as well as adding a few of my comments and suggestions at the end. I know, it’s a cop out, but hey, this information has been repeated ad nauseum all over the web, as the original research has been completed long before I ever came into this world. Besides, I don’t think my one subscriber would mind a quick blog post, thanks again Mom.

Boron (B):

Stimulates cell division, flower formation and pollination.

Chlorine (Cl):

Important in photosynthesis, stimulates root growth and aid in water transport.

Copper (Cu):

Stimulated stem development and pigment formation

Iron (Fe):

Stimulates formation of chlorophyll and helps oxidize sugars for energy.  Necessary for legume nitrogen fixation and regulates cellular respiration.

Manganese (Mn):

Important in chlorophyll formation.

Molybdenum (Mo):

Nitrogen fixation and use in the plant.

Nickel (Ni):

The newest micronutrient to be recognized as an essential nutrient. Required for conversion of urease to urea, releasing ammonia for plant nitrogen use. Also required for iron absorption, seed production and germination.

Zinc (Zn):

Stimulates stem growth and flower bud formation.


Non-essential Micronutrients (although beneficial)


Vanadium (V):

Partially replaces Molybdenum’s function in plants.

Cobolt (Co):

Improves plant growth, water circulation and photosynthesis.

Silicon (Si):

Strengthens the cell wall and important in seed production.

It is my opinion, based on strong research, that all micronutrient and most macronutrient amendments can be satisfied by the addition of an inch or two of good, quality compost every year. I do, however, appreciate that sometimes there is a need for other amendments based on soil quality and specific nutritional needs of the plants.  I have listed below general balanced organic amendments that should cover most, if not all micro and macronutrients for the average gardener.

1. Compost

2. Worm castings

3. Fish emulsion

4. Kelp meal

5. Rock Dust

How do I use amendments?

In the fall I start making most of my compost for the spring tilling and raised beds from manures and leaf mulch. I have a supply of horse manure and this is the primary source that I use, along with the manures from my chickens and turkeys. I would love to use a more ruminated manure such as cow, but that stuff is literally like gold in my area, and the Amish just wont give that stuff up. I do supplement with what chicken manure I save, but with only 10-30 birds at any given time, it certainly isn’t enough as I plant roughly 1/4 acre of garden each year, not including multiple fruit shrubs and about a dozen fruit trees. I do have future plans of raising rabbits, pigs and maybe a cow or goats, but that is not in the near future, at least not in 2016-17, so I make due with what I have, and more importantly, whats free.

 

In the spring I start my seeds in a self made mix of peat moss, worm castings and crushed egg shells. This gives my seedlings a jump start on the season with the only amendment better than compost (worm castings), calcium to prevent blossom end rot (I plant 75 – 100 tomatoes plants and 25 – 50 peppers), and the peat moss to make it all a fluffy mix on the acidic side, for which most plants like. I will also add a 1-2 inch layer of compost in my raised beds, or 20-30 gallons per 100 square feet in my ground beds.

During the growing season I may spray my plants about every two weeks with a mix of fish emulsion, seaweed emulsion and epsom salts.   This really gives them a boost and finishes off any nutritional needs they may have.

At the end of the growing season, or when any of the beds are not planted with crop, I will incorporate a cover crop. Depending on the time of year, the crop previously planted and future considerations, I generally choose between a legume (clover is my favorite), buckwheat, winter rye, or a general mix if leaving the bed rest for any length of time.

As this “Growing Soil” series wraps up, I will add one final session, Part 6, Cover Crops.

 

 

Sources other than embedded into links in the blog body:

Pennsylvania State Extension

http://pss.uvm.edu/ppp/pubs/oh34.htm

The Maryland Master Gardener Handbook

The Self-Sufficient Life and How to Live It (Seymour)

The Vegetable Gardeners Bible (Smith)

The Truth about Garden Remedies (Gilman)

What’s Wrong With My Vegetable Garden? (Deardorff & Wadsworth)

What’s Wrong With My Fruit Garden? (Deardorff & Wadsworth)

https://www.ghorganics.com/page32.html

http://www.cias.wisc.edu/wp-content/uploads/2008/07/soilorgmtr.pdf

Growing Soil (Part 4)

We know that there are 17 recognized nutrients that are considered essential for plant growth with three of them being carbon, oxygen and hydrogen. These three elements are acquired from the air, leaving 14 elements remaining. Of these remaining 14 elements, six are considered macronutrients, and the other eight are considered micronutrients. There are three primary macronutrients (nitrogen, phosphorous, and potassium) and three secondary macronutrients (calcium, magnesium and sulfur). Generally speaking the primary macronutrients are typically applied to soil as fertilizer as they are usually in heavy demand by plants.

MACRONUTRIENTS

Most fertilizers will be labeled in a way to show N-P-K values (Nitrogen-Phosphorus-Potassium) as the principal ingredients unless they are specific for other macro/micro ingredients, such as Calcium (Ca), Magnesium (Mg), etc.  The N-P-K is represented by a percentage value by volume. For example an amendment such as cotton seed meal with a N-P-K value of 6-3-2 will be 6% nitrogen, 3% phosphorus and 2% potassium. A one pound application of this product to your soil will add ((1.0 lb x 6% (0.06)) 0.06 pounds of nitrogen.

Nitrogen (N): Nitrogen exists in multiple forms but can only be used by plants in three specific forms (nitrate, ammonium/urea, and amino acids). Nitrogen is used by plants to form amino acids and proteins and is essential in forming structural and metabolic compounds.

Symptoms of nitrogen deficiency include yellowing and chlorosis of mature leaves and slower plant growth.

Nitrogen along with phosphorus is a major contributor to contamination of surface and groundwater.

Organic nitrogen amendments include: COMPOST!, Blood meal, alfalfa meal , animal manures, cottonseed meal, feather meal, fish emulsion, soybean meal, and green manures (legumes), and coffee grounds.

Phosphorus (P): Phosphorus is usually bound with another substance in our soil and is generally dependent upon soil pH. In soil with a pH above 7, phosphorus is generally bound to calcium, and in soils below 5.5 the binding agent is usually iron and aluminum. When the soil pH is between 5.5 and 7 the phosphorus “bind” isn’t as strong and becomes more readily available for plant uptake.

Phosphorus is the primary energy carrier in the plant cell and is vital to maintaining the cell wall membrane. Phosphorus also assists to regulate many enzymatic activities.

Symptoms of phosphorus deficiency include abnormally dark green or purple leaves and stunted root growth as evidenced by an increased root:shoot ratio. Phosphorus toxicity can also interfere with the iron that is available to the plant as well as minimizing the uptake of copper and zinc. High phosphorus concentrations in soil will decrease the mycorrhizal (Fungi) growth, thus inhibiting the symbiotic relationship that creates healthy plants that produce more fruit.

Organic amendments of phosphorus include COMPOST!, animal manures (cow, horse, chicken, rabbit, goat), bone meal, and mushroom compost.

Phosphorus is more likely to be bound to soil elements than nitrogen as it is not as freely exchanged through the atmosphere.  Because of this, phosphorus is likely more of a contributor to water contamination and algae blooms due to soil runoff into our streams and lakes, and ultimately larger bodies of water such as the Chesapeake Bay.

Potassium: Potassium is highly bound to soil elements unlike nitrogen. Plants take up more potassium comparatively speaking, than other nutrients, other than nitrogen. Plant tissue generally shows a ratio of N:K as 1:1. Vital functions of potassium include plant metabolic activity via regulating water status and the opening and closing of the stoma. Potassium is also important in plant carbohydrate production as well as cellulose formation.

Symptoms of potassium deficiency are rare due to the high mobility in the plant itself. Some signs of low potassium would include yellowing of leaf edges and eventual necrosis called scorch.

Generally speaking there is no potassium toxicity to plants, however overabundance of potassium can lead to reduction in the availability of magnesium and calcium.

Organic sources of potassium include: COMPOST!, greensand, kelp, wood ash, tobacco stem, and soybean meal.

Sulfur: Sulfur is found mostly in organic form, rather than mineral. Sulfur is utilized by the plant in amino acids, protein, vitamins, and other compounds specific to giving distinct vegetable flavor i.e. onions and mustards.

Symptoms of sulfur deficiency are similar to nitrogen (yellowing of leaves, although sulfur will be apparent on younger leaves while nitrogen typically presents on older leaves). Generally speaking there is no sulfur toxicity in plants as it is immobile once incorporated into plant tissue.

Sulfur is not commonly added to soil as an amendment outside of incidental additions via compost, etc., however elemental sulfur is a key organic amendment when lowering soil pH. Sulfur takes several months to reach the desired effect on lowering soil pH, so it must be used several months in advance of planting.

Organic sources of sulfur include: COMPOST!, gypsum or elemental sulfur.

Magnesium: Magnesium is often found in abundance in soils, but is not generally associated with organic matter as it is typically in mineral form. Eventually it is weathered and made available to plants and is taken up by plant roots.

Magnesium is an important component of the chlorophyll process.  Magnesium deficiency typically presents as interveinal chlorosis, or a yellowing of the space between the veins of the leaf, while the veins remain green.  Generally there is no magnesium toxicity.

Organic sources of magnesium include: COMPOST!, epsom salts, and in trace amounts found in fish meal, green sand and dolomitic limestone.

Calcium: Calcium comes from calcium containing minerals such as apatites, gypsum, and carbonates.  It is important in cell wall integrity and membrane stability.

Early signs of calcium deficiency may be noted as small distorted young leaves with curled tips as well as stunting of shoots and roots. Calcium deficiencies noted as late signs generally present in the nightshade family specifically in peppers, tomatoes and watermelon, causing blossom end rot. Calcium toxicity in the plant interferes with magnesium and potassium uptake, mimicking Mg and K deficiencies. Calcium overuse in soil can interfere with phosphorus, manganese, boron, zinc uptake as well as increasing soil pH.

Organic sources of calcium include: COMPOST!, crushed eggshells, gypsum, and dolomite lime.

So that is an overview of the macronutrients important in growing healthy soils, and ultimately happy plants. Again, my opinion is that compost should be considered an essential amendment that should be added to your garden each year, specific supplements should be added only when needed as observed by symptoms, soil testing or planting of know heavy feeders of a particular nutrient.

It has been my observation over many years of growing, that simply adding compost every year to your garden, should be all you need to have fantastic production from your garden.

Up next: Micronutrients

 

 

Sources other than embedded into links in the blog body:

Pennsylvania State Extension

http://pss.uvm.edu/ppp/pubs/oh34.htm

The Maryland Master Gardener Handbook

The Self-Sufficient Life and How to Live It (Seymour)

The Vegetable Gardeners Bible (Smith)

The Truth about Garden Remedies (Gilman)

What’s Wrong With My Vegetable Garden? (Deardorff & Wadsworth)

What’s Wrong With My Fruit Garden? (Deardorff & Wadsworth)

https://www.ghorganics.com/page32.html

http://www.cias.wisc.edu/wp-content/uploads/2008/07/soilorgmtr.pdf

Growing Soil (Part 3)

Soil Testing Basics

As I mentioned in the previous post growing soil should be done in a responsible way.  The very first step in adding any amendment, is knowing what you need, not what you think you need. This process starts with a soil test. A proper soil test will be able to confirm or deny your suspicions regarding your soil health. It will test for pH, macronutrients, micronutrients, electrical conductivity potential, salt contents, etc. Knowing what you need before you add it will save you time, effort and money as well as being environmentally responsible.

Time and effort: Adding just what your soils needs saves time in multiple applications of amendments you do not need.

Money: If your soil is at optimal N-P-K levels, why would you spend the money to add more, when your vegetation can only utilize so much.

Environmentally responsibility: See Previous Post

I am a huge proponent of utilizing your state extension office services for research and advice concerning anything that grows. Your state Master Gardeners are a wealth of knowledge and are generally eager to help answer any questions that you may have. Having said that I am very disappointed in my states soil test reporting.  The basic information is available, but it does little to explain these results to the average person and how it applies to their scenario. This report is not intuitive and in my opinion can be difficult to understand for new gardeners or experienced gardeners who are new to soil testing. To me this lack of intuitive reporting may actually be a deterrent to gardeners to have their soil tested, if they have to struggle to understand the results. The best resource I have located to date, explaining the components of spoil testing can be found at The University of Massachusetts.

Soil test basics

1. Tests should be completed on a yearly basis for basic testing, i.e., N-P-K, Ca, Mg,  pH, CEC and organic matter. If you utilize large amounts of fresh or composted manure, salt testing may be beneficial, as this can compound with annual use.

2. Soil tests give information regarding a measurement of plant available nutrients, relative nutrient status, and nutrient recommendations.

3. Once a soil test program is chosen, your should utilize the same testing center every year as the testing procedures may differ significantly between sites and may alter your impressions of the test.

4. Follow the recommendations of the soil test to bring your soil into optimal levels.

5. Some testing centers offer standard fertility testing and a number of specific additional elements may be at an additional cost. Make sure you understand what your particular sample will be tested for prior to sending it off.

6. Many extension offices offer manure and composting testing as well.  This may be a valuable tool to understand the value of the inputs you are using to predict any future nutrient deficit or abundance.

Next up: Organic Soil Amendments

Resources:

Pennsylvania State Extension

http://pss.uvm.edu/ppp/pubs/oh34.htm

The Maryland Master Gardener Handbook

The Self-Sufficient Life and How to Live It (Seymour)

The Vegetable Gardeners Bible (Smith)

The Truth about Garden Remedies (Gilman)

What’s Wrong With My Vegetable Garden? (Deardorff & Wadsworth)

What’s Wrong With My Fruit Garden? (Deardorff & Wadsworth)

Growing Soil (Part 2)

Soils and Fertilizers

In part one we defined soil, soil texture as well as structure and the components thereof. We dipped briefly into pH and its affect on soil organisms as well as the importance of  nutrient uptake. We outlined a simply approach to healthy soil by utilizing adequate water, organic material and aeration. The next logical step would appear to describe the basics of soil amendments (fertilizers) and organic matter. However, I think we need to discuss this in a different light before we move on.  Lets take a look at what we do wrong, before we review what we can do right

Soils as Hydrologic Buffers.

As you can see from this graphic, this is the cycle of water and soils potential to buffer it. Realistically there is no end or starting pointgroundwater, but to simplify things, lets start with precipitation. During a rain event, plants uptake water to meet their needs, surface runoff leads to the water table, ground water and surface water filling and eventually leads to aquifer recharging over time. Plants contribute to condensation (cloud formation) through transpiration. Water hitting the ground leads to infiltration then percolation through the soil. In almost every step of this process evaporation is occurring as well, recharging the sky in the form of condensation and the process is continuously recharging and filtering.

Soils as Biochemical Reactors

nitrogen-cycle
Nitrogen Cycle

The best example of biological reactors I can think of is the
nitrogen cycle, unfortunately it is also one of the most complex. In a much more complicated process than hydrologic buffering, nitrogen goes through a similar process where one form in the atmosphere is taken into the ground by animal and atmospheric fixation and deposition. Basically plants like clover and other legumes fix nitrogen through their root structure and animals well…..again doing what animals do…  In a multi-conversional process nitrogen is broken down into ammonium and nitrates for plants to be able to utilize and uptake through their root system. Crops and vegetation are harvested and plant residuals release nitrogen back into the atmosphere, and we start all over again.

There is a problem with this given the fact that this is not a closed system. There is loss of nitrogen through ground water runoff and leaching. This often ends up in our water supply and eventually into our lakes, streams and oceans. Inappropriate use of nitrogen fertilizers and manures contribute significantly to this nitrogen excess and is considered a pollutant in high volume areas. Before assigning blame to the farmers and growers in rural areas, we should understand that data has shown that per acre, there are more pollutants in the form of nitrogen, phosphorus and pesticides from homeowners, golf courses, and public places utilizing high content fertilizers and ignoring the potential actual repercussions of these choices. There has been significant damage to the ecosystems of the Chesapeake Bay and its subsidiaries due to nitrogen, phosphorus, and pesticide runoff. Nitrogen pollution has affected all wildlife in the surrounding areas as seen by significantly decreasing numbers of aquatic life over the last several years.

Algae Bloom

Soils have variable effect as a filter especially for overused fertilizers, organic or synthetic. Soils are not effective filters for negatively charged particles (anions) such as nitrates, chlorides, bromides and fluorides.  These anions have a weak negative charge and are repelled in the soil by stronger negatively charged particles in clay and significantly contribute to runoff. Think of this as two magnets approaching each other with each of them leading via their southern pole. One magnet is significantly stronger than the other and like poles will repel each other with the stronger magnet pushing the other away. This is not the case however for soils and positively charged particles (cations). Soils are effective at holding cations like calcium and magnesium and some stronger anions such as phosphates. In a perfect world (nature), there is a delicate balance of inputs and outputs but again the issue here is over use of these elements, especially nitrogen and phosphates. The soil simply gets saturated and cannot hold onto these elements that are used in excess and are leeched out and eventually lost into the water systems causing significant issues as described previously as well as large algae blooms that have a significant impact on the river and lake ecosystems as seen in this photo.

HOW DO WE FIX THIS?

So how can we mitigate this response?  Responsible amendments.

soil-testThe first place to start is a soil test. A basic soil test can be completed through your state extension program, for usually under $10. If you are considering amending any type of soil, a soil test can give you exact specifications as to what elements you actually need, otherwise you are guessing. Unfortunately, we are often guessing more wrong than right with indiscriminate fertilizer applications. Routinely spreading 10-10-10 on your garden or 48-0-0 on your lawn is simply irresponsible. This significantly contributes to watershed issues as well as damaging the soil structure. Eventually the “little bit” of synthetic (salt based) fertilizer that gets spread on your garden, grass, etc., doesn’t work like it used to, or worse, if a little works well a lot will be better, right?  So we end up using more fertilizers not realizing that it’s not necessarily an issue with a lack in soil nutrition, but the damage to the soil from poor soil management that is inhibiting growth. Eventually the soil microbes and invertebrates will decrease in numbers die off and contribute even more to poor soil conditions through poor soil management.

There are less intrusive, more responsible ways to manage vegetation around your home. Did you know that not raking up your lawn clippings and leaving them lay will return almost 50% of the nutritional feedings needed in a year?  There are also other ways to finish amending a lawn such as corn gluten meal or compost, just to name a few. If applied in the spring just as the forsythia starts to turn yellow, you may likely eliminate weed sprouts from germinating as well as feeding your lawn.

The next step, as hinted in the previous paragraph is using responsible organic amendments. Corn gluten meal, replacing grass clippings, composting, oyster shell and eggshells for calcium, fixing nitrogen through legumes, not synthetic fertilizer, are just a few examples.

Synthetic fertilizers are like fast food to plants.  They may work in the short term and satisfy a need, but think what happens long term. Try eating a Big Mac and fries every day for a year and see what happens, I think you get the point.

Summary:  A common sense approach to growing soil can have tremendous effects on your vegetation as well as protecting our waterways and surrounding wildlife. Know what you are putting down (organic hopefully) only after you know how much you need through soil testing. These simple steps can go a long way in reversing the damage that has been done as well as building fantastic soil life.

NEXT UP: Soil Test Basics

RESOURCES:

Pennsylvania State Extension

http://pss.uvm.edu/ppp/pubs/oh34.htm

The Maryland Master Gardener Handbook

The Self-Sufficient Life and How to Live It (Seymour)

The Vegetable Gardeners Bible (Smith)

The Truth about Garden Remedies (Gilman)

What’s Wrong With My Vegetable Garden? (Deardorff & Wadsworth)

What’s Wrong With My Fruit Garden? (Deardorff & Wadsworth)

duoinc.com

nutrients.utah.gov

soil.ncsu.edu

treehugger.com

Growing Soil (Part 1)

There is an old adage that poor gardeners grow weeds, good gardeners grow vegetables and great gardeners grow soil. I’d like to talk about growing great soil with the byproducts being healthy plants. This will be a multi part series covering the very basics of growing healthy soil.

It would seem the most logical place to start would be defining soil. Soil is compromised of three basic components, solids, liquids and gasses.  Solids may be a combination of organic materials or mineral deposits, liquids are typically soil solutions comprised of water and dissolved particles, while soil gasses (soil air) is generally comprised of atmospheric gasses trapped under the soil line. There are three major zones of soil, Topsoil, subsoil, and rock/sediment. Today we will be primarily concerned with topsoil, or the O and A horizon which contains most of the plant needed nutrients for plants to survive.

SOIL SOLIDS

As previously stated, soil solids are mostly organic materials and minerals.  These solids form the porous catacombs that allow the liquids and gasses to live and perform their vital functions. Yes, I did say live, more on this later.

The major mineral classes in soil are made up of sands, silts and clays. No need to get into the particulars of these particles as their mineral sizes range from less than 0.002 mm (clays) to 0.05 – 2 mm (sands), with silt being somewhere in between (0.002 – 0.5 mm). These components form the soil texture, which by the way are recognized by twelve (12) textural classes (See below) according to the USDA, based upon their particular mix and proportions of sand, silt and clay. Strangely enough, organic material has no relevance in the classifications of soil texture, but it is vital in the role of soil structure, as it is the glue that holds the mineral particles together. Soil structure is the arrangements of soil particles into aggregates, or clumps, and can be improved or diminished based on the result of (good or poor) soil management.

Organic materials are comprised of biomass, residues and by-products as well as humus. Organic materials typically make up only 2 to 5 percent of most solid material in soil, but is vital to productivity of vegetation and soil life. Soils that have acceptable levels of organic material give the soil increased ability to hold water and nutrients as well as oxygen resources to be made available for plant absorption. Some of the very best soils that I have ever seen have organic material in the 10% or more range. In a nutshell, the more organic materials in the soil, the more nutrient rich the environment is for plant absorption. This nest statement could literally be the most important aspect of growing soil. If you increase the organic material in soil, you increase the soil fertility, thus growing great soil with the byproduct being healthy and productive pants. The most effective way you can add organic materials?  Compost! Compost! Compost!

SOIL SOLUTION

Soil solutions are the products of water and dissolved materials. They are essential for providing hydration and nutrients to plant materials. Soils solutions are in a constant state of ebb and flow based on the availability of rain/irrigation, and nutrient content (organic materials) based on the soil health and structure. Generally speaking most healthy soils thrive on one inch of water per week, based on normal conditions, normal for me being in zone 6B. Those of you in more extreme climates would obviously require an adjustment to this criteria. Sandy soils will require more water, while heavy clay may require less.

An important aspect of nutrient availability to plant material and soils is often overlooked, the pH. pH (percent hydrogen) is a logarithmic scale indicating the acidity (pH below 7) or the alkalinity (pH above 7) of soil from a range of 0 – 14, with 7 being neutral. Plants can be very fickle in regards to pH; if it is not within their specific desired range, they simply cannot take up nutrients, no matter what your soils health status is. The soil pH is important to plant growth in several ways by affecting: (1) soil bacteria, (2) nutrient leaching, (3) nutrient availability (4) toxic elements and (5) soil structure. An example of this would be the blueberry and the beet. I love them both but wouldn’t think of growing them in the same space as blueberries generally like a soil pH of 4.5 to 5.5, and beets thrive is soil closer to neutral (7) or even 8. Reverse the soils surrounding these plants and you may have some limited growth, but no where near the production that you would in a more appropriate soil.

The graph shown here may be a little difficult to conceptualize initially, but it does paint a great picture of pH and plant absorption of nutrients. The elements are listed in the colored bands.  The numbers on the bottom correspond to soil pHsoil-ph.  The thicker the band, the more available the nutrient. For example, take phosphorus (P), it is readily available to plants when the pH is between 6 and 8, as well as above 9. For this post, disregard the pH near or above 9, as this is not compatible with life for most plants, if not all plants and is only relevant in academia. Notice how the line thins between 8 and 9 and below 6? This means the element (P) is not as available under these conditions as it would be with a more appropriate pH level. Remember, this is not describing the amount of element in your soil, but the soils ability to use this particular element based on the specific pH. Take note that most of these elements are readily available between a pH of 6-8.  We can conclude from this, that generally speaking if you pH is between 6 and 8, your plants should do fine.

SOIL AIR

Soil air is generally similar to that of the surrounding atmosphere but is slightly higher in carbon dioxide and lower in oxygen. Soil air is generally comprised of the following elements: Nitrogen (79%), Oxygen (20.9%, Carbon Dioxide (0.035%) and traces of other atmospheric gasses. The major issue affecting soil health in regards to soil air are compacted soils (less air) that create an anaerobic (lack of oxygen) environment thus decreasing the oxygen availability to the plants, diminishing the available oxygen for healthy microbes (aerobic) and creating an environment more suitable for pathogens (typically anaerobes). There are also the issues of diminished root growth and poor drainage in compacted soils.

Summary: Growing soil is multifaceted and can be as complex as you want it to be. It can also be a simple as you want it to be by understanding the basics of healthy soils and following a common sense approach: adequate water, aeration and organic matter.

Next Up: Soils and Fertilizers

 

Resources:

Pennsylvania State Extension

http://pss.uvm.edu/ppp/pubs/oh34.htm

The Maryland Master Gardener Handbook

The Self-Sufficient Life and How to Live It (Seymour)

The Vegetable Gardeners Bible (Smith)

The Truth about Garden Remedies (Gilman)

What’s Wrong With My Vegetable Garden? (Deardorff & Wadsworth)

What’s Wrong With My Fruit Garden? (Deardorff & Wadsworth)

Its-Summertimefun.com

nwdistrict.ifas.ufl.edu

terragis.bees.unsiv.edu.au

An Introduction to Compost

I have made a concerted effort to increase my composting this fall in order to try to be as free of amendments (always organic) in the next growing season as I possibly can. I have read many studies that continue to say that a one to two inch cover of compost may be all you really need for healthy soil, and ultimately healthy plants. Multiple research studies also show that the very best compost is made from fall leaves, and that’s it. For some crops with a higher nitrogen requirements, additional amendments with manures or organic amendments may be helpful. For most gardens, fall cover crops will enhance your garden as well.

I previously posted several ways that I make compost, but in order to make as much as possible, I will be using the most efficient way I know how, dump it and flip it. I have added horse manure to fall leaves to create an “immediate heat” for my soil next year with my major goal of growing sweet corn. I have tried growing sweet corn in the past with mixed results. The very first year, I had great results, but there has been a significant decrease ever since. The first year was in virgin ground with years, and years of natural nitrogen fixing from clover, etc., and manure as this was an accessory field for our horses. It soon became nitrogen depleted no matter how many cover crops I grew and organic amendments I applied. This garden was fine for other vegetables, even heavy feeders such as pumpkins and potatoes, but just didn’t fit the bill for sweet corn.

The following is a summary from Abigail Maynard’s research (The Connecticut Agricultural Experimental Station in New Haven) COMPOST: The Process and Research:

“Using compost in the garden has many benefits. For most vegetables and cut flowers, recent research at The Connecticut Agricultural Experiment Station has shown that fertilizer can often be eliminated when the soil is amended annually with 1 inch of leaf compost. However, optimum yields are obtained when leaf compost and some inorganic fertilizer are used, usually half the normal rate, and after 2 or 3 years of consecutive compost amendments. Optimum yields can also be achieved using compost and organic fertilizers but they are generally less effective, especially on sandy soils. For vegetables that demand higher amounts of nitrogen, a cover crop incorporated into the soil in addition to the leaf compost amendment may be necessary for optimum yields. Compost is most effective when applied in the spring before planting. For optimum results, leaf compost may be applied every year, especially in sandy soils, and can also be safely applied at higher rates if compost is available.”

Admittedly, some of this research is old, greater than 25 years in some cases, but it is still applicable today considering it is specifically concentrating on leaf compost, manures and organic amendments. There is some mention of inorganic amendments as well and referring to their use as gaining “optimum yields.” but again, this research is old in this regard as it has been proven time and time again in multiple studies, that the same or better “optimum yields” can be achieved with an organic approach. As far as I know, trees still drop their leaves, animals still….. well you know, and organic amendments have remained relatively unchanged over the last several years. Maynard’s research is a short read, but really packed full of good information regarding composting.  Enjoy.