If you are a gardener you are quite familiar with compost and it’s benefits. Even if you don’t garden you’ve probably heard of compost and know that it is beneficial, and you may have bought bags of compost for use in your yard.
Uses for Compost
Compost is a nutrient rich soil additive that will replace the depleted elements of soil where something – anything – has been growing. Vegetables, flowers, fruit bushes and trees, even your lawn benefits from adding compost.
Normally compost is mixed into the soil to boost its nutrient content, but for things like trees and lawn, where disturbing the soil is not practical, a top dressing allows rains to leech nutrients down into the soil below.
For lawns, use a manure or compost spreader to lay a thin layer (1/3” is good) over the grass in late winter or early spring. The compost will fall down between the leaves of grass so it doesn’t crush it down or block the sun. Then, when the spring rains come the water carries nutrients down to the roots to kick-start your lawn.
If you don’t have access to a spreader, you can sprinkle compost with a shovel, then use a garden rake turned upside down (tines pointing up) to spread it out.
Components of Compost
The basic ingredients of good compost are green materials, brown materials, water and air.
What makes the difference between a green product and a brown product is the carbon to nitrogen ratio, not its color. Ingredients with high nitrogen content and a carbon to nitrogen ratio below 30:1 are greens. Ingredients with a higher carbon content are browns.
Green materials are plant waste: grass clippings, fruit and vegetable kitchen scraps, and most garden wastes. Do not include grass clippings if the lawn has recently been sprayed with weed killer; wait until you’ve mowed two or three times after the treatment to compost the clippings. Also try not to include weeds with seed heads on them.
Brown materials are woody plant products, paper, cardboard, straw, fallen leaves and sawdust. Grass clippings that have dried out may look brown, but they’re still considered greens because all they’ve lost is water. Bedding from herbivorous animals like rabbits, guinea pigs, mice, and hamsters is good too because their droppings are rich in nitrogen. Never add droppings from carnivorous animals like dogs or cats, any diseased plants, or any oils.
Cutting or tearing your ingredients into small pieces increases surface area and opens more soft surfaces to invasion by the microbes that will turn them into compost. Cutting up large green leaves, crumpling or shredding dry leaves, chipping sticks and branches and tearing up paper and cardboard will speed the process and make managing the pile easier.
The microbes that convert these ingredients into compost require moisture and air to do their work. As for moisture: it doesn’t take much; you don’t want a sodden compost pile, just moist – about like a wrung out sponge. Misting the pile with the hose every couple of days will probably be sufficient.
Air is required to grow the right kind of enzymes. Aerobic microbes grow in an oxygenated environment, they will feed on the greens and browns, growing and reproducing in the pile and turn that material onto compost. Anaerobic microbes do much the same thing, but they prefer an environment with lower oxygen content, they work more slowly and they stink.
If your compost pile smells like a garbage dump it isn’t getting enough air. It may be too wet or it may need to be turned more often.
Turning Your Compost
You can make compost by simply throwing your ingredients into a container or a pile and leaving it set for a couple of years. However, by turning the compost regularly you will get better compost, faster, and without the smell.
There are many ways to make compost. You can simply make a pile on the ground. Every week or two use a garden fork to roll the pile over so what was on top is now on the bottom. This mixes the ingredients and aerates the pile at the same time.
There are many kinds of bins: wooden, plastic and metal that will contain a compost heap. Even a cylinder of metal wire fencing works well. Lift the contents out with a fork or lift the bin off to roll the pile.
Or you can buy (or make) compost tumblers. Some roll on the ground, some set on a frame with rollers, some include cranks and gearing. Some claim to produce compost faster and with less fuss than other methods. Whether that’s true or not is a matter of debate.
Two important things to consider when choosing a compost container or bin: it needs to allow fresh air in, and you want to let it sit long enough that the heap reaches an internal temperature of 150° to kill off weed seeds and speed the decomposition. Rolling a tumbler every day may interfere with this cooking.
Proportions are Important
The next thing you want to consider is the amount of greens and browns you add to a pile. As you build a pile, you want to add 2 to 3 times as much brown materials as greens. In the spring and summer greens are plentiful; but if you just pile in grass clippings, banana peels and melon rinds, the pile will turn to a soggy, smelly mess quite quickly. Procuring enough browns to keep the ratio right may be a problem. Chipped up branches, straw and sawdust work well – although don’t use black walnut sawdust because this tree contains juglone which will inhibit growth and may kill plants such as tomato, potato, blackberry, blueberry, azalea, mountain laurel, rhododendron, red pine and apple.
When adding materials to the compost pile or container, add thin layers of greens and browns: 1 part green to 2 or 3 parts brown. And it doesn’t hurt to mix them up with a fork before you leave. Because browns are dry, you’ll also want to water the pile a bit to moisten it. Remember: not soggy, just moist.
A proper compost pile should have a sweet, woodsy smell to it. If the smell is unpleasant it is either too wet or too high in green content. In either case the remedy is to add more browns and mix them in well.
The Final Product
When the compost is competed, you will have a pleasant smelling, crumbly brown or black product. If there are large bits, you can sift them out with metal mesh (hardware cloth) and put them back into the next batch to finish the process. You may also find earthworms in the compost; they help the process and their casings add enrichment to the compost.
If you follow the recipe and are diligent in stirring or rolling the pile to keep moisture and aeration at proper levels, you will end up with a high quality compost that will greatly benefit your lawn and garden. And by using grass clippings, tree trimmings and kitchen waste you’re recycling these trash items into something useful. Not to mention saving money because you won’t need to go buy bags of compost if you make your own. It’s a win-win, all around.