Composting Leaves: How to Achieve Fast Leaf Decay
Let’s get real for a second: composting leaves is one of the smartest things you can do for your garden. It’s a great way to mulch, fertilize, and generally improve your soil. There are tons of different ways to approach it too!
If you haven’t gotten into it yet, or don’t know where to start, this is for you. Get ready to know everything you’ll ever want to know about how to compost dead leaves so that your leaves decay quickly and turn into beautiful, rich leaf compost!
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Why Should You Compost Leaves?
Leaves are great sources of nutrients and minerals. Up to 80% of a tree’s nutrients and minerals end up in its leaves. Leaves are often referred to as nature’s nutrient recyclers. By composting leaves, you have a perfect way of getting these valuable nutrients and minerals back into your soil.
They’re free! If you have trees in your garden, you will know that come fall you are almost buried in fallen leaves. Learn to take advantage of this free source of goodness for your garden.
If you don’t have trees in your garden, why not ask a neighbor or friend with trees? Many people would happily pass on a few bags of leaves, especially if you help out with some of the leaf collection! You can also ask a local landscaper. They are often happy to donate bags of leaves as it saves them time and money in tipping fees.
Leaves provide a high carbon source or ‘browns’ for your compost. The carbon/nitrogen (or C/N) ratio of leaves is usually over 30, often around 50. That is, they are low in nitrogen which is often hard to find in other sources of composting material.
Common Problems With Composting Leaves
There are two main issues you might run into when trying leaf composting:
Leaves have a tendency to mat, particularly un-shredded leaves. Matted leaves create an impenetrable barrier to air and water and thus significantly slow decomposition. Be sure to shred your leaves if you’re going to compost them.
Leaves take a long time to break down. Leaves contain varying amounts of lignin. Lignin is resistant to decomposing, meaning that green leaves can often take a year or two to fully decompose.
4 Ways to Deal With Leaves In Your Garden
Here are four great ways to get the most out of your yard waste in your garden. The approach that works best for you and your garden will depend on the volume of leaves you get, the space you have to handle them and how long you want to decompose them. We’ll start off with composting, and then suggest a few other ways to deal with them if you want a few more ideas.
1. Make Compost
Composting leaf matter takes more time, patience and effort than simply making mold. But if you have the space and time, then yard waste leaves can be a great way to make extra compost for your garden.
Note that not all leaves are created equally. Some leaves compost more effectively than others.
Good leaves for compost: The best leaves for composting are those lower in lignin and higher is calcium and nitrogen. These leaves include ash, maple, fruit tree leaves, poplar, and willow leaves. These ‘good’ leaves will typically break down in about a year.
Bad leaves for compost: Bad leaves are those higher in lignin and lower in nitrogen and calcium. These include beech, oak leaves, holly, and sweet chestnut. Also, make sure to avoid using leaves of black walnut and eucalyptus as these plants contain natural herbicides that will prevent seeds from germinating. Leaves of diseased plants should also be thrown away and not composted.
However, the juglone contained in them should break down in a couple of months. Therefore you’re safe to compost oak leaves and then use them on your garden after a few months.
How to Compost Leaves
Firstly, shred or grind the yard waste leaves. This will significantly speed up the decomposition process. If you don’t have a shredder, you can simply use your lawn mower mow the leaves to collect them. Alternatively, a garbage can and a string trimmer will work (be sure to wear eye and ear protection). Fill your garbage can approximately three quarters full with leaves. Put your string trimmer in, turn it on and move it through the layers of leaves.
Leaves are considered ‘browns’ in your compost pile or compost bin. Therefore you need to add liberal amounts of ‘green’ materials or organic matter, high in nitrogen, such as grass clippings or kitchen waste. To prevent attracting pests to your compost pile and to speed up the composting process, bokashi composting is a great way to pre-compost your food waste. Mix 4-5 parts leaves to one part green waste.
Adding compost accelerator, like green organic waste to your large pile will add a boost of microbes to help the composting process.
Turn your pile 1-2 times a week. Add more green waste (grass clippings, kitchen waste etc) as you turn. Turning the pile and mixing in oxygen will get it to heat up and compost more quickly. Remember to keep the pile moist. It wants to be the consistency of a sponge. Covering the pile with a plastic sheet will help to keep the pile warm and prevent it from drying out.
If you keep up the regime of regularly turning and aerating your pile you should have high quality leaf compost by the following spring.
Extra leaves can be stored in sacks next to your compost pile. These can be added to your compost pile as brown materials to balance the green materials and aerate your compost pile throughout the year.
2. Add Directly To Your Garden
The first, and easiest, option is to add them directly to your soil as a top dressing soil amendment. This will help to keep your soil (and plant roots) insulated over the winter. Covering bare soil with leaves over the winter (such as unused vegetable gardens) will protect the soil from heavy rains and winds that may erode the soil and leach out important nutrients.
Tip: Chop in a layer of bokashi pre-compost (or other green waste such as grass clippings)
3. Use to Protect Containers
Leaves can also be used to protect containers from harsh winter temperatures. Cluster your containers together and cover with leaves, including the top and sides of the containers.
Tip: If your containers are in a windy location, use chicken wire to hold the leaves in place.
4. Make Leaf Mold
Leaf mold is the soft, cushiony layer found naturally in the forest just above the soil. It decomposes slowly and adds nutrients gradually to feed plants and improve the soil structure. This mold is not as rich in nutrient value as completely composted leaves but it is easier and quicker to make.
Mold from leaves makes a useful mulch around the garden and has a fantastic ability to retain water. A good quality topsoil can retain moisture at around 60 percent of its weight in water, but leaf mulch can hold between 300 and 500 percent of its weight in water! Therefore, careful it doesn’t provide excess moisture to your plants.
Making Mold From Leaves
Make a large container for your leaves. A circular compost bin made with livestock wire or snow fencing is cheap and simple to make. Add your leaves and dampen. Done! It’s that simple.
The finished compost should be ready to use the following spring or summer, although some people choose to store theirs for several years.
Tip: Mold from leaves is slightly acidic so add ground limestone to your compost ingredients if your plants are sensitive to acidity.
Frequently Asked Questions
Q: What leaves should not be composted?
A: Try to avoid leaves that have a higher lignin content. Also, remember that you should wait at least two months before using compost that has juglone-containing leaves. You don’t want to spread herbicide on your crops unintentionally.
Q: Can I compost just leaves?
A: You can. indeed! The result is a healthy mulch or garden soil enricher.
Q: What is the fastest way to compost leaves?
A: Shred them first, and then hot compost them in a compost pile with high nitrogen containing plants like grasses and coffee grounds. They’ll break down most quickly this way.
Q: How long does it take for leaves to compost?
A: It takes roughly two to four months for leaves to break down adequately enough in a compost pile or in a pile of their own.
Q: Are rotting leaves good for compost?
A: They really are! It acts as an carbon source for your compost.
Q: Do leaves need to be shredded for compost?
A: They don’t have to be, but shredding will speed up the process.
Q: Are rotting leaves good for soil?
A: Yes. They decompose and feed nutrients to your garden soil, just as they do on the forest floor.
Q: How do you compost large amounts of leaves?
A: Use the quick leaf compost method we discussed above, adding nitrogenous plant clippings, food scraps, and other kitchen scraps like coffee grounds to the leaf pile. Effectively, you’re making a compost pile.