Composting is a great way to improve your garden soil and recycle plant waste. Composting requires very little time and space, and benefits plants, the soil, and the environment by minimizing waste.
Put simply, compost is decayed organic matter. Composting can be managed very simply and can involve as little as piling discarded plant material – like banana peels, carrot leaves and peelings, and garden waste – into a pile. With a little management, you can turn the parts of plants that would normally go into the trash into a rich, loamy soil amendment that works wonders in your garden. Adding compost benefits the garden by helping the soil retain water, improving drainage and aeration, supplying nutrients, and increasing biological activity of soil organisms
Four key factors will make a successful compost pile: a good ratio of green to brown material, high temperatures, frequent turning of the pile, and adequate moisture.
The first step to creating a compost pile is designating a location for composting. Easy and close access to your garden or kitchen is important (a compost pile shouldn’t smell bad if managed correctly). You can simply designate a place for your compost area and start piling plant waste there, but some gardeners will choose to create wooden bins or other systems for their compost to help speed up the process. If your compost pile is spread out too thinly, it will not generate enough heat to break down the plant material (at least not quickly). How much plant waste you generate will determine how large your pile will be, but a good starting size is about three cubic feet. You want to build the compost pile up so that it has a chance of getting hot in the middle.
To make a successful compost pile, there are a few things that you need to keep in mind: a good ratio of green to brown material, high temperatures, frequent turning of the pile, and adequate moisture.
Green and Brown Materials
When adding plant waste to your pile, you want to have a good ratio of green to brown material – about one part green to three parts brown. The green material – grass clippings, plant leaves, coffee grounds, eggshells – are high in nitrogen. The brown material – dead leaves, pine-straw, corn stalks– are high in carbon. After you’ve added the green material, which is what most of your garden and kitchen waste will be, top with a layer of brown material. This will help keep your pile from attracting animals and from smelling.
Organic matter – like discarded plant material from your garden – breaks down in a compost pile by getting very hot. Insects, fungi, and microorganisms like bacteria are hard at work in a compost pile, consuming and breaking down the materials there. Through this process, the bacteria release carbon dioxide, and the pile gets warm. A warm compost heap is a good sign that the process is working. You can buy a soil thermometer to probe the inside of your compost pile to check that the pile is getting warm enough – 135 to 160 degrees F is a good range. However a soil thermometer isn’t necessary, and if you have the right materials and a good-sized pile, it should get warm enough. In the winter, the composting process is slowed, but you can continue to add to the pile and turn it in the spring when it gets warm enough.
Turning the Pile
Turning the pile is as simple as it sounds: using a hoe or garden fork to move the compost material around so that the material on the top gets mixed in. The hottest part of the compost pile is at the center, so frequent turning of the pile ensures that the material is being broken down evenly. Smaller particles also break down more quickly, so it’s a good idea to use a hoe or another garden tool to break down larger plant waste that you add to the pile (like the woody stems of cabbages and kales get tossed in at the end of the season).
It’s essential to keep your compost pile moist to keep the process moving. The hard-working microorganisms need water to break down the organic matter. If the compost pile gets dry, water it. You don’t want it to be too wet, but the material should be about as moist as a wrung-out sponge.
What Can’t Go in the Compost?
Nearly all of your plant waste can go in the pile. However, don’t add diseased plants or weeds that have gone to seed to the compost. Unless the pile gets very hot, the seed likely won’t die and when you spread the compost on your field, you will also be spreading weed seeds. You also should avoid adding meat, cooked foods, oils, dairy, and bones to your pile. Some of these things won’t break down (or will break down very slowly), and others will attract unwanted animals.
Adding Compost to Your Soil
When your compost is finished decomposing, it should be dark and loamy. The length of time it takes for a compost pile to finish varies greatly, depending on the outside temperature, the size of the materials being added to the compost, the size of the pile, and the frequency of turning. A compost pile could be finished in as few as three months. Before the growing season starts and after you’ve prepared your beds, you can add a one to two inch layer of compost on top of the soil and plant directly into it.
After your compost pile has enough material and is starting to break down, it’s a good idea to start a new pile and allow the existing pile to finish decomposing.
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