Without a source of nitrogen, the leaves will not become compost, but will instead become leaf mold, a valuable addition to the soil in terms of drainage and water holding capacity, but not as valuable as mineral-rich compost.
Leaves are good for making compost out of. Leaves contain carbon, nitrogen, and water, which plants need. They are also biodegradable, and their nutrients are easily accessed by plant life. Moreover, compost made from leaves helps to ensure the nutrients of an area do not leave it.
The leaves themselves do not improve the soil, which is what all composters strive for (but they create leaf mold, a valuable addition to the soil; below).
Best Practices for Making Compost with Leaves
Using freshly fallen leaves to create mold or compost not only preserves the mineral content of the leaves, but also increases the function that transfers that nutrition from the soil to the plants. Using fall leaves that easily turn into protective mulch, soil-improving foliage, or rich compost is the gift of the fall seasons to the composter.
For dry leaf compost without the use of green material, Iowa State University’s Extension and Disclosure says you should place the leaves in 30-gallon plastic bags with 1/2 cup nitrogen fertilizer, two shovels of garden soil, and a quart or two of water.
If you’re new to composting, keep in mind that the decomposition process works best if you mix equal volumes of carbon-rich, naturally dry plant material (fall leaves, dry grass, straw, and wood cuttings) with nitrogen-rich green plant material. (grass clippings, withered flowers, greenery clippings, weeds, and cuttings of fruits and vegetables).
I add these leaves to my working compost heap throughout the year to balance food waste and other materials that are normally rich in nitrogen. However, before they can be used for soil modification, dried leaves must be decomposed through composting.
Making a Traditional Compost Pile
To make a traditional compost pile, mix dry leaves and other brown materials with nitrogen-rich green plant materials such as fresh grass and plant waste. But composting leaves isn’t as easy as picking up a bunch of leaves next spring and spreading them out in the garden. Composted leaves that are not chopped and not mixed with a green nitrogen source can last for years before they rot. But to get the most out of leafy nutrients, we recommend using compost.
If you have a large supply of leaves, we recommend using containers, cages or piles to start the composting process. Dried leaves are rich in carbon, an important component of composting. By November, I usually run out of steam and just put the remaining whole leaves in the compost bin. Most of them end up in plastic trash bags that hide in the barn until next spring when I use them as mulch in my perennial gardens.
Lessons Learned from Composting
Over time, the crushed leaves turn into something called leaf mold, which makes a wonderful mulch. The leaves are full of trace elements that trees extract from the bowels of the soil. They will not only save you money on buying mulch, but will also help enrich the soil, retain moisture and protect plants from temperature extremes in winter. As I clean the beds, I cover the ground with a layer of crushed leaves and wag a little.
The bed is given a healthy dose of granular fertilizer and then covered with a 3-inch layer of crushed leaves. Luckily, fallen leaves can find new life in our gardens with some basic preparation. Collect a bunch of organic materials and leave it for a year when the compost is finally ready to use.