Composting leaves is an excellent way to give your compost and your garden a boost. However nearly everyone runs into a problem when trying to compost leaves. Here is a quick preview of what's ahead here.
Composting leaves, especially tree leaves is great for both your compost and your garden.
Most trees have long roots extending deep into the subsoil. They draw in the nutrients and trace minerals which have leached out of the upper soil layers.
Fifty to 80% of these nutrients end up in the leaves so you'll find tree leaves rich in trace minerals. They are nature's nutrient recyclers.
Most leaves provide a high carbon source or "browns" for your compost. In other words their C/N ratio is usually over 30, often around 50. Essentially this means they are low in Nitrogen. In a compost they'll need their nitrogen rich green counterparts.
If you were to believe everything you read about composting I have to think you'd feel betrayed by the leaves in your compost. The word out there would have you believe that by mixing your leaves with a few greens, in a couple of weeks you'll be spreading a nicely rotted compost on your garden.
Not, I'm afraid. That huge pile of leaves you're coping with in the fall are tough cookies. They contain varying amounts of Nitrogen, Lignin and Calcium. A whole winter's time in the compost bin and there's a good chance your leaves will look exactly like they did when you added them.
Leaves have two problems in a compost:
Leaves are collectively categorized with a C/N ratio of around 60. This places them firmly in the 'browns' or high carbon category of the compost pile. Their actual C/N ratios range from around 20 to over 100.
It isn't just the C/N ratio that tells how your leaves will perform in a compost. Decomposition is linked to the relative amounts of nitrogen, lignin and calcium they contain.
According to Ken Thompson, author of Compost (whose book I love for its straight forward info and humor), these are useful categories to use when composting leaves.
Okay - so your leaves are sometimes slow to breakdown and have a tendency to mat. These are the two problems you want to try to resolve in your compost and here's how.
I've used two different leaf shredders and really like them. They are fast. You might consider getting one to share with neighbors. I take mine to the community garden in town to shred a bunch of leaves for our compost there.
I also like the idea of those reusable leaf bags both for carting pre shredded leaves to your shredder and storing the results. And of course an outdoor trash can to store beside your kitchen compost bin so you can balance the compost as you add your bits.
Many experienced composters choose not to mix their fallen leaves into their composts. They instead handle them separately creating a special compost made from almost 100% leaves called leaf mold.
It's simple to make leaf mold. Just follow these steps