Sustainable Soil building for organic gardening begins after the initial garden soil testing and the addition of fertilizers and conditioners. It is very important to maintain and improve the soil when trying to garden organically. Sustaining the soil means that you have a means of replenishing the garden soil with what you have at hand – compost, beneficial microbes, enzymes, and earthworms. Ideally, once your organic garden is established it could be sustained with garden compost alone - by removing garden soil and layering it in your compost. This method uses the microbes in your soil to inoculate your compost, which in tern will feed your soil.
Composting improves soil structure and moisture retention. Billions of decaying organisms (25,000 bacteria placed end to end equal one inch) feed, grow, reproduce and die, recycling garden waste into an organic fertilizer and soil conditioner. Composting is the ultimate recycling process – improving soil structure, increasing the soil’s ability to hold moisture, providing soil aeration, fertilization, and nitrogen storage. It buffers pH, releases nutrients, and provides food for microbial life.
Shreded Alfalfa Hay is one of the secrets of great compost. It is worth it to rent a shredder for the weekend, and shred up a few bales of alfalfa hay. Worms thrive on it, and it provides the best mulch and soil additive for your garden soil.
Builing Your Compost Pile
Build your compost pile about four feet in diameter, and four feet high, on a well-drained site. A ring of hog wire with a ring of chicken wire on the outside of it works well - providing air circulation, keeping the pile contained, is easily taken apart for turning or sifting, and, it is economical and very easy to maintain. We let our piles set for a year and then sift them in the spring when we are adding compost to our garden beds. No Turning! If you want to turn your pile, let it set 3-4 months, remove the wire and set it up next to your pile. Take the pile apart, mix it, and add it to the new pile, moistening it as you go. You may do this as often as you like. This will speed up your composting process.
First layer on the bottom should be about three inches of roughage – corn stalks, brush, or other materials to provide air circulation.
Second layer is two to four inches of dry vegetation – carbon-rich "brown" materials, like fall leaves, straw, dead flowers shredded newspaper, shredded alfalfa hay or dry manure. Water well.
Third layer should be two to four inches of green vegetation – nitrogen-rich materials, like grass clippings, weeds, garden waste, vegetable peelings, tea leaves, coffee grounds, and crushed eggshells. Kitchen waste may be added but never use meat scraps, diseased plants, dog or cat manure, or poisonous plants, plant-based kitchen waste. Water until moistened. (Too much water will compact your pile and reduce available oxygen.)
Fourth layer is garden soil, two inches thick. It is important to add garden soil because it contains a supply of microorganisms and nutrients, which will inoculate your compost pile. As microorganisms grow, they collect essential nutrients containing antibiotics, vitamins, and catalytic enzymes in their body tissues and release them slowly as they die and decompose.
Repeat layers of dry vegetation, green vegetation, and garden soil – moistening each layer – until the pile is three or four feet high. To insure enough green vegetation one can plant extra garden greens, or devote one of the garden beds to the growing of compost. Good composting greens are broccoli, cauliflower, kale, comfrey (grow it in an isolated spot, and do not disturb the roots, because it can be invasive), peas, beans, and all the rest of the garden weeds and greens.
Cover the top of the compost pile with three to four inches of garden soil, making a ridge around the outside edge to prevent the water from running off. Use a broom handle or iron bar to make air holes from the top, deep into the pile every eight inches or so, for ventilation and water. Top off the pile with two inches of shredded alfalfa hay. Water regularly to keep moistened.
Cured compost has almost all the nutrients the crops contained, and so many beneficial microbes that it is one of the best things you can do for your garden. It also contains enough humus to replenish your soil’s supply. Your compost is ready when it is dark, rich looking, broken down, crumbles in your hand and smells like clean earth. Parts of the compost pile along the outside edges that have not completely broken down will be removed when your pile is sifted and can be placed at the bottom, and between the layers of the next compost pile.
Sifting compost is easily done by placing a 4 x 4 foot square of ½ inch wire mesh over your wheelbarrow and bending the edges over the sides. Then a shovel full of compost may be placed on top of the wire mesh and rubbed. The siftings fall into the wheelbarrow and the lumps will remain on top. One side of the wire can be lifted from the wheelbarrow and these clumps will fall to the ground into a pile. When you are done, these can be shoveled into a new compost pile, and be layered accordingly.
Problems can occur if conditions areunfavorable. Some of the problems are:
Bad odors indicate that there is not enough air in your pile. Make more air holes in your pile, or turn the pile, or start a new one.
Center of compost pile is dry means there is not enough water in your pile. Make more air holes, and fill them with water, and the water will disperse throughout the pile.
Compost pile is damp, but only warm in the middle indicates that your pile is too small. Increase the size of your pile to at least four feet high and four feet wide.
Compost pile is damp and sweet smelling, but remains cool indicates a lack of nitrogen, not enough green matter or manure. Cover the pile with black plastic for a few days, but be careful not to cook all your microbes. The pile also may need more water.
Speeding Up Composting
To speed up composting process and increase the decomposition rate you can add extra nitrogen, fishmeal or blood meal, to your layers. Using a metal rod to make holes in your pile will increase the amount of oxygen and stimulate aerobic activity. You can also shred your components fine, which causes faster decomposition. Compost inoculants can also be used to add nitrogen fixing, decomposing, and other soil bacteria, enzymes and hormones.
Vermi-composting is another organic gardening technique, which uses earthworms to make compost, which will be rich in organic matter and worm castings, and is one of the best soil builders available. Worms can eat their body weight daily in organic matter and convert it into dark, soil enriching castings full of live micro organisms, growth hormones, and nutrients, humic acids which condition the soil, and a neutral pH. Worm castings are free from disease pathogens, which are killed in the process. They prefer a temperature range of 60 to 70 degrees, but will tolerate 32 – 84 degrees. They require a moist, pesticide free environment with plenty of organic matter to eat. There are two types of Vermi-composting, indoor and outdoor.
Outdoor Vermi-Composting, Above or Below the Ground
Above the ground bin: composting red worms are an excellent addition to a compost pile. The worms help to process the pile by eating the decayed matter and turn the waste into fine topsoil in approximately 2 to 3 months, depending on the quantity of worms introduced into the pile, the outside temperatures, and the time of year. A compost heap that is 4 x 4 x 4 should have a minimum of 3,000 to 10,000 worms introduced into the pile – about two pounds. Add them to your compost pile when it has broken down and is warm but not hot in the center. Dig down about a foot and add the worms. Keep the pile moistened, but not soggy wet. This pile will be your “breeding area”.
When you want to remove some of the worms for next compost pile, begin feeding the worms at one spot near the edge, and when the worms move to this area after a few days, add some of the worms to your other compost pile. At this time you can also remove some of the soil and worm castings for your garden lowering your pile a foot or so. Keep feeding the worms in the breeding area by adding greens and shredded alfalfa hay to the top of the pile every few weeks. Be sure to add four or five inches of shredded alfalfa hay for winter protection, and keep the pile moistened, but not wet.
Below the ground bin: Dig a 2x8 foot trench two or three feet deep into the ground below frost level. Place a six-inch layer of peat moss and shredded newspaper or cardboard on the bottom, and water until evenly moistened, but not soggy wet.
Fill the bin ¾ full with a mixture of 2/3 corrugated cardboard and 1/3 sphagnum peat moss, shredded newspaper, shredded leaves, or shredded alfalfa hay, add a little crumbled aged or composted manure, and a cup or so of fine sand mixed with equal parts of wood ashes, and ground limestone. Mix well, moisten, and add two to three inches of a mix of finely chopped vegetal kitchen wastes, garden waste, and aged manure to one end of the pit.
Add one pound of red compost worms, which can be ordered through the mail. (When your worms first arrive they may be dehydrated, you can feed them a light dusting of corn meal before you cover them.)
Loosly cover worms/waste with a 2-inch layer with shredded alfalfa hay. Water and feed two or three times a week – adding vegetable waste under the alfalfa layer to keep the process going. Each time you feed your worms place the waste mix next to the previous feeding area, working your way toward the opposite end of the pit. When you get to the end of the pit, feed back towards the beginning. As you continue these layers and reach the top, leave a four-inch space between the cover and the mixture for ventilation.
Cover the top of the pit with a sheet of plywood to keep out the elements and critters, and weight down with rocks.
In a few months and under the alfalfa layer you will have worm castings, which can be transferred to your garden beds. To harvest your worm castings wait until the worms are being fed are at one end of the pit. You can remove the castings from the opposite end of the pit. Replace the castings with the mix of 2/3 corrugated cardboard and 1/3 sphagnum peat moss, shredded newspaper, shredded leaves, a little crumbled aged or composted manure, and a cup or so of fine sand mixed with equal parts of wood ashes, and ground limestone. Cover with the 2-inch layer of damp shredded newspaper or cardboard mixed with straw.
Indoor Worm Bins
Compost can be made indoors by using wood, metal or plastic bins with lids. Special worm composting bins may be ordered through the mail, or you can easily make your own. Special worms are used in Vermicomposting: Eisenia foetida or Lumbricus rubellas, which can be ordered from worm farms, or some nurseries. Start with about a pound or worms, around 1000. They can multiply quickly, and the surplus can just be added to your summer garden, or given to friends.
Build or Buy a Box
For two people, a box 2’ x 2’ x 8” deep, or so, wood, metal, or plastic, will suffice. For a larger family, make it 2’ x 3’ x 1’ deep. There should be some small ¼ “ holes in the bottom for drainage, and the box should be set on a tray with 1” spacers between the tray and the box, for aeration and drainage.
Line the bottom with shredded 1-inch strips of newspaper, inch wide strips of cardboard boxes, and peat moss. A mix of 2/3 corrugated cardboard and 1/3 sphagnum peat moss, or newspaper, is a good bedding mixture. You can also add shredded leaves and a little aged or composted manure, and a cup or so of fine sand, ashes, and limestone. Moisten the bedding, mix it well, and add the worms. Let it set for a few days before kitchen waste is added. Your worms will happily feed and make castings.
Add kitchen waste every day or so, by burying it a few inches or so in the bedding mix in one end of the box. Kitchen waste can include: vegetable and fruit scraps, coffee grounds and the filters, tea bags, without the tags, any vegetable matter, bread scraps, dried and crushed eggshells, and small amounts of finely chopped meat scraps, garlic and onion.
Cover the top of the compost bedding with a layer of damp newspapers, and a loosely fitting lid with holes for air. Every time you add waste, work your way to the other end of the box, so you will have about 8 or 9 different adding areas. When you get to the end of the box, start over at the other end. Worms will eat the bedding along with the scraps, and you may need to add more. Keep the bedding mix/scraps moistened, but not soggy wet. In a few months you will be ready to harvest your compost.
To harvest compost castings, follow the same procedures for gathering outdoor castings. Only add the castings to your garden beds, these special worms live indoors only.
This article originally appeared on Giannangelo Farms Southwest website, www.avant-gardening.com: "YOU CAN GROW!" using sustainable organic gardening as a medium for creative expression and spiritual growth. Extensive sustainable organic gardening information, workshops, monthly newsletter, organic gardening CD's, virtual tours, links/resources, and more.