Monday, May 11th, 2009...12:00 am
Leaves as Fertilizer
TheGardenLady received this question from Marvin.
I like your article on using leaves as fertilizer. What specific nutrients are added and how much? I use them in my garden and have sugar maple leaves.
By recycling leaves you are doing what nature does. But leaves by themselves take a long time to break down. Especially maple leaves which can become compacted and suffocate plants if left whole on your plants. So if you just want to use leaves, make them into mulch. Rake the leaves into a pile. Then you can use your lawnmower as a mulcher and mow over the leaves until they are particle sized. Or you can buy a mulcher to do this. This is easiest in the fall when the leaves are brown and dry. Spread the leaves as you would mulch. There are some nutrients in the leaves when used this way and as the leaf mulch works down into the soil it helps make the soil more friable ( crumbly).
Or you can make compost with the leaves. Save the leaves in an out of the way place or build or buy composting bins to hold the leaves. You don’t have to add nutrients, there are some nutrients in the leaves. But to make your compost quicker, you will have to do a little more than just save the leaves. You will want to add grass clippings and household garbage to the leaves.
Microbial activity is affected by the carbon-to-nitrogen (C/N) ratio of the organic waste. Because microbes need nitrogen for their own metabolism and growth, a shortage of nitrogen will slow down the composting process considerably. Material high in carbon relative to nitrogen, such as straw or sawdust, will decompose very slowly unless nitrogen fertilizer is added. Tree leaves are higher in nitrogen than straw or sawdust, but decomposition of leaves still benefits from an addition of nitrogen fertilizer. Grass clippings are generally high in nitrogen and enhance decomposition when mixed properly with leaves. Manure, cottonseed meal, or blood meal can be used as organic sources of nitrogen. Otherwise use a high nitrogen- containing fertilizer. You need an initial C/N ratio of about 30 parts carbon to 1 part of nitrogen. C/N ratios below 25:1 may give off ammonia odors and above 35:1 will take longer to compost. Other nutrients such as phosphorus and potassium are necessary, but are usually present in adequate amounts for decomposition.
Follow the directions here.
You will want to add water to the C/N mix and will want to turn the mix. Some of the purchased bins have a device to turn the barrel. But save your money and use a pitch fork with a little muscle. By getting air in the mix you are heating the mix so that your compost will decompose quicker. Good composting with be hot and you might even see steam even coming out.
By making compost with the mixture of leaves, grass and garbage, you will be making a rich soil to give back to the earth that which was depleted. Your plants will be so thankful.