Compost is one of the best mulches and soil amendments available, easiest ways to feed your garden soil and can (and should) be used instead of commercial chemical fertilizers. It is easily improved or customized for your specific garden conditions and best of all, compost is cheap. You can often make it without spending anything, or very little. Using compost improves soil structure, texture, and aeration and increases the soil’s water-holding capacity, while at the same time improving it’s drainage. All you need is some feedstocks, moisture and time.
Compost loosens clay soils and helps sandy soils retain water. Adding compost improves soil fertility and stimulates healthy root development in plants. The organic matter in compost provides food for the microorganisms that digest and break down the matter, which keeps the soil in a healthy, balanced condition. Feeding of the microorganisms also make foundational minerals more readily available to the plants such as nitrogen, potassium, phosphorus, boron, silicon, magnesium and trace elements. Well fed, properly produced compost applied to the garden soil will create a condition where few if any soil amendments will need to be added.
We will examine several aspects of compost and techniques to build the nutrient value of the compost for the garden. One of the most useful aspects of compost is it’s adaptability, as it can be “customized” or enhanced with many additions that will increase it’s fertility and value to the garden. This is not meant as an introductory how-to compost article. There are several great articles on the web for that. We recommend the article at Organics for All- Composting Guide. This will get you started in the right direction, and you can use the techniques shown here to customize your compost for your garden’s needs.
For our discussion, we will assume a manure based compost, combined with leaves or straw for the close to ideal 25-30:1 ratio of carbon to nitrogen (C/N). Here are some examples the C/N ratio for common compost feedstocks-
This is taken from the Organics for All article Composting Guide.
One of the common techniques of the Genetic Engineering industry is called “Stacking”, or combining several traits into one variety to try to achieve multiple benefits. I’m not sure if it works, but the same thought pattern can be applied to our compost, with results that don’t need to be studied for a decade or two to determine if they are indeed dangerous. We will be looking at and discussing several of these techniques, all of which can be “Stacked”, or combined to achieve greater benefits. Some of these techniques are common use in the garden, and will have similar effects in the compost pile.
Mineralization- If you’ve followed the previous soil building blog posts, you understand the importance of adding minerals to your garden soil, and the incredible benefits it has. For those who haven’t read it, read Mineral Restoration of Your Garden Soil for the first part and Mineral Restoration of Your Garden Soil Part II for the second. Adding a broad based mineral supplement to your compost will kick-start the decomposition and feeding of the microorganisms, and give them a powerful, healthy start. This will carry over when you apply the compost to your garden, as the remainder of the minerals and trace elements will benefit the garden soil, your plants, veggies and ultimately- you.
Mycorrhizal Fungi- An ancient microscopic group of fungi that develop symbiotic relationships with about 90% of crop species. They colonize in and around the roots and root hairs, sending out hyphae- strands that are about 1/25 the diameter of a human hair- into the surrounding soil anywhere from 15 to 25 inches. This increases the nutrient “reach” of the plant from 10x to sometimes 100x! Mycorrhizae create enzymes to mobilize and release phosphorus, nitrogen, zinc, iron, calcium, magnesium, manganese, sulfur and several other nutrients from the soil and transport them to the roots of the host plant. They also produce antibiotic and other defensive compounds that fight damaging root diseases by other fungi and bacteria.
Molasses- From Wikipedia: Molasses is a viscous by-product of the processing of sugar cane or sugar beets into sugar. Sulfured molasses is made from young sugar cane. Sulfur dioxide, which acts as a preservative, is added during the sugar extraction process. Unsulfured molasses is made from mature sugar cane, which does not require such treatment. There are three grades of molasses: mild or barbados, also known as first molasses; dark, or second molasses; and blackstrap. The third boiling of the sugar syrup makes blackstrap molasses. The majority of sucrose from the original juice has been crystallized and removed. The calorie content of blackstrap molasses is still mostly from the small remaining sugar content. However, unlike refined sugars, it contains trace amounts of vitamins and significant amounts of several minerals. Blackstrap molasses is a source of calcium, magnesium, potassium, and iron; one tablespoon provides up to 20% of the daily value of each of those nutrients.
Molasses is a very valuable addition to the compost pile, as well as to the garden itself. Unsulfured blackstrap is the preferred variety, due to the mineral content, but any of the unsulfured ones will do fine. The benefits beyond the minerals are the natural sugar content that will feed the microorganisms in the compost or soil of the garden. Use one cup to a gallon of water and spray onto the pile, or add to the drip system of the garden. The readily available sugar content will skyrocket the microbial activity. Blackstrap molasses is also commonly used in horticulture as a flower blooming and fruiting enhancer, particularly in organic hydroponics. Use the before mentioned mixture in the drip system, or sprayed alongside the roots of fruiting vegetables as they start to flower to increase their flowering and fruiting.
Milk-Using milk on your compost and in your garden will probably come as a surprise to most. Upon closer inspection, however, it starts to make sense. The amino acids, proteins, enzymes and natural sugars that make milk a food for humans and animals are the same ingredients in nurturing healthy communities of microbes, fungi and beneficials in your compost and garden soil. Raw milk is the best, as it hasn’t been exposed to heat that alters the components in milk that provide a perfect food for the soil and plants. Using milk on crops and soils is another ancient technique that has been lost to large scale modern industrial agriculture.
Recently a Nebraska farmer completed a 10 year study on applying milk at different rates to his pastures, and recorded the results with the help of the local Agricultural Extension agent, a university soil specialist and weed specialist. What they found was amazing- the grass production was drastically increased; the soil porosity or ability to absorb air and water doubled; microbe activity and populations increased; cows were healthier and produced more milk on treated pastures; the brix or sugar level in the pasture tripled, indicating more nutrients were stored in the grass than before. Grasshoppers abandoned the treated pastures- the sugars are a poison to soft bodied insects as they do not have a pancreas to process the sugars. This also explains why insects will leave healthy, high brix level plants alone, as they contain more sugars than the stressed and sickly ones.
The ratio can range from 100% milk to a 50/50 mixture with water, with no loss of benefits. Use as a spray on the compost and garden soil prior to planting, and as needed when insects appear. Spray directly on the insects and around the areas they inhabit.
Manure- Earlier, I had said the assumption was a manure based compost. Manure is usually available, even if you don’t have horses or cows. If you get to know farmers at the Farmer’s Market, or growers that sell in your area, most have animals and that usually means excess manure. Most folks with animals are happy to have someone pick up their excess manure. The more different animals that contribute to the compost pile will ensure a healthier and more diverse population of microbes and critters in the pile, meaning a better, healthier compost. Horses are not ruminants, so their manure is pretty much just chopped grass and alfalfa. It decomposes well and provides a good compost. Sheep and cattle are ruminants, so their manure has been broken down further and has a lot of beneficial bacteria and microbes that will jump start the compost. When these are combined, you get the best of both- to your soil’s benefit!
Coffee Grounds- Another unusual but highly beneficial and productive addition to your compost. The grounds of already brewed coffee are usually about pH neutral, yet have shown to have a great buffering capability. This simply means that if you add coffee grounds to acidic or basic soil, it will help to minimize the acidic or basic effects and bring the pH back toward neutral, about 7.0. Grounds are a Nitrogen source for the 25:1 C/N ratio, so depending on what feedstock is being used, coffee grounds can be very valuable to keeping the decomposition moving along. The upper limit on grounds is 25%, so a LOT of coffee grounds can be added if needed! Worms absolutely love coffee grounds, so this acts as a “worm attractant”.
So, now that you’re considering adding coffee grounds to your compost, where in the world do you get them? Your office or work is a good start, as well as home. Starbucks has a corporate policy of working to reduce waste, so they usually have a covered bucket next to their stand that they put the used grounds in. The paper filters are compostable as well, being that they are usually unbleached paper. Coffee shops, diners, restaurants and donut shops are also great resources. If you feel funny asking for coffee grounds, you will probably be surprised when they respond enthusiastically when they understand what you’re trying to do.
Charcoal or BioChar- This is another of the soil building articles previously written. Please read Terra Preta- Magic Soil of the Lost Amazon for part one and Terra Preta Part II to get up to speed. Charcoal needs to be hard wood or lump, not briquettes and should be crushed to smaller sized chunks, about the size of a corn seed. It needs time to “activate” where it absorbs minerals and trace elements as well as providing a home for the microbes, beneficial bacteria and fungi that make the compost so nourishing to the garden. Charcoal will last at least 100-300 years, so it isn’t something that will be depleted quickly. Adding it in small amounts to the compost, and thus to the garden for several years will only increase the health, fertility and productivity of your garden soil each year.
Work with what you have. You may not have a lot of nitrogen (green) or an abundance of carbon (brown) ingredients. Use what you have readily available. It’s not complicated, if you don’t have the “correct” ratio, just substitute some time and everything will be just fine. Use the above chart and this article to get the ratio close, and don’t sweat the small stuff. The gentle folks in India have been composting for something like 5,000 years without compost tumblers or fancy enclosures. Work with your local conditions- for instance we have to water our compost to keep it alive.
Now you can see what is meant by “Stacking” of these techniques! Compost by itself is very valuable, but when combined with some or all of these techniques, things will really start moving, and in a positive direction! The health and fertility benefits will increase exponentially, and not only once, but each time the compost is added to the garden soil, which should be twice a year- in the Spring prior to planting and again in the Fall. This creates an ever increasing spiral of benefits for the garden, the plants, the fruits and vegetables and of course for you and your health.
This proves what Sir Albert Howard said to the House of Commons in England at the end of the 19th Century when he said, “As goes the health of the soil, so goes the health of the nation.” He was laughed out of the House of Commons, but we are realizing now, 120 years later, that what he said is absolutely true. Improve the health of your soil, and your health will be improved from the produce of your garden.