The Short Answer. In most cases, a compost pile does not need a cover. Unfinished compost breaks down into a terrific soil additive if the pile is uncovered the whole time. Only three things are necessary for effective composting: air, water and a blend of brown and green material.
Insulate the Pile
Insulate compost in order to keep it from freezing solid and halting decomposition. Compost bins can be surrounded with bags of leaves or straw bales to buffer against freezing temperatures. Another option is to ring the inside of the bin with 6-12 inches of leaves, sawdust or woodchips.
The pile should not be directly exposed to sun, wind, rain, nor sited in a low-lying place subject to unnecessary dampness and standing water. Strong sun not only dries, but also is hostile to micro-organisms.
Cover your manure pile with a heavy tarp and good weights to hold it down against strong wind. You will keep the beneficial nutrients and you will not be polluting streams or groundwater.
In the compost production process, windrows should be covered. There are different reasons to do this depending upon the season. During rainy seasons, a cover prevents moisture from damaging the compost.
Covering a compost heap with a hay tarp traps heat and moisture in the pile. This speeds up the decomposition process considerably. You can do even better by removing the tarp from time to time, turning the pile over, soaking it with water, and putting the tarp back on.
Composting works in sun or shade Piles in sunny spots will decompose quicker but also dry out faster and may need supplemental watering during hot dry weather. Those located in a shadier spot will stay moist longer but decompose slower.
As a rule of thumb, actively decomposing materials should be turned every three to four days. Materials with slowed microbial activity can be turned less often. In tumblers, turning two times a week resulted in higher temperature and faster decomposition than turning once a week or once every other week (Figure 1).
Test whether the compost is ready...
Decomposition will be complete anywhere from two weeks to two years depending on the materials used, the size of the pile, and how often it is turned. Compost is ready when it has cooled, turned a rich brown color, and has decomposed into small soil-like particles.
You can put your compost pile in the sun or in the shade, but putting it in the sun will hasten the composting process. Sun helps increase the temperature, so the bacteria and fungi work faster. This also means that your pile will dry out faster, especially in warm southern climates.
You may be surprised to learn that your compost pile needs just as much water as your live plants. Dry compost doesn't work. There are several ways to ensure your compost is getting the adequate amount of water needed to do its job.
If your compost is too wet, it will have a soggy feel. In the worst case, it will also give off an unpleasant sweet sticky smell like ammonia. The consequences of having too much moisture in your compost are that the composting process will be interrupted, slow down, or completely stop!
After the pile reaches around 80-90 degrees Fahrenheit, you want to stop adding greens and limit the amount of browns so that the compost can cure. Keep turning the piles regularly to add oxygen.
Compost should not be stored for years since it starts to degrade once the decomposing process has passed its peak. Finished compost should be used within about 3 to 6 months maximum. Storing compost correctly is essential to maintaining the mix's valuable nutrients and microbes.
Banana peels are a great ingredient for your compost or worm farm, adding lots of nutrients to the organic recycling process.
Another issue of soils that receive excessive compost is the potential for increased soluble salts to levels that would cause salt toxicity. In high tunnels, soluble salts can accumulate to excessive levels because leaching is minimal. Composted manure is generally higher in salts than composted vegetative matter.
Weeds have many nutrients so they are a great addition to the compost pile, but you do not want compost filled with viable weed seeds. The best time to take care of weeds is when they are small and have not established deep roots or seed heads (easier to pull, too, especially if ground is still moist).
When you need compost quickly, a covered pile is the way to go. A covering holds heat in the pile, which helps the good bacteria to work more efficiently. The cover effectively speeds up the process, shaving weeks (and even months) off the time required to produce finished compost.
Compost is ready or finished when it looks, feels and smells like rich, dark earth rather than rotting vegetables. In other words, it should be dark brown, crumbly and smell like earth.
Almost everyone advises putting down a layer of coarse material — corn cobs and husks, sticks, thick fibrous stalks from vegetables, or tall flowers. This layer improves aeration at the bottom of the compost pile.
Insulation, such as flattened cardboard, old carpet or polythene sacks filled with straw will help retain this heat. It's also important to stop the winter heap becoming overly wet, so covering the bin is vital.
Composting Don'ts
Don't add fish, meat, dairy products, bones, baked goods, fatty foods or grease to your compost pile. These food scraps do not easily decompose and may attract animals. Don't use diseased plants or plants that are toxic to other plants.