Friday, November 14, 2008

Leave the leaves

It's going to be a rainy weekend, and not much good for raking, but if you haven't already raked the fallen foliage, you may want to read this article forwarded by new correspondent, Reporter Fang.

Let Leaves Feed Your Soil

by Jean English
Copyright 2008

Looking for free "fertilizer" for your lawn or garden?

Look to leaves! Leaves that drop in the fall can supply all the nutrients needed in a vegetable garden. They'll even supply a wider range of essential nutrients than a bag of 10-10-10 synthetic fertilizer, because tree roots draw over a dozen plant nutrients up from the soil and deposit them in leaves. Bags of synthetic fertilizer, on the other hand, often contain just three essential plant nutrients: nitrogen, phosphorus and potassium.

So, instead of thinking of leaves as waste that needs to go "away," think of your yard as a source of nutrients, a green manure crop, for your garden.

The University of Florida ( found that "good yields of such crops as cucumbers, tomato and greens can be expected after 2 to 3 years of applications of at least 20 tons [of oak leaves] per acre annually." That's a little under 5 pounds per 100 square feet.

Some people worry that adding leaves to the garden will tie up nitrogen that crop plants need. This won't be a problem if you add leaves as a mulch in the fall (especially if you've shredded the leaves by running over them with a lawnmower), so that soil organisms and weather move them into the soil slowly. Also, including grass clippings with leaves adds nitrogen to the mix, further reducing the chance of nitrogen deficiency, as does mulching the garden with additional grass clippings throughout the summer.

If you don't have a garden to receive leaves, or you don't have a lawn mower that catches clippings and leaves, just leave the leaves on the lawn, mowing them a few times during the fall to shred them. Denise Ellsworth of Ohio State University Extension writes, "Research has shown that lawns can absorb many pounds of shredded leaves with no detrimental effects." She says that Purdue researchers mowed 2 tons of leaves per acre into turf grass annually for five years. They saw no increase in disease or weed problems and no pH or nutrient-availability issues. Microbial activity did increase-a sign of improved soil quality. ("Leaves benefit gardens as compost and mulch," Akron Beacon Journal, Nov. 10, 2007).

Decomposing leaves improve soil structure so that it absorbs more moisture during rains and holds that moisture better during dry spells. Your lawn will stay greener longer in the summer.

If you don't want to mow and shred leaves, you can rake them into compost piles and make leaf mold-a good substitute for peat moss in the garden and in potting mixes.

This article is provided by the Maine Organic Farmers and Gardeners Association (MOFGA), PO Box 170, Unity, ME 04988; 207-568-4142;; Joining MOFGA helps support and promote organic farming and gardening in Maine and helps Maine consumers enjoy more healthful, Maine-grown food. Copyright 2006. Please let us know if you reprint this article. Thanks!


Anonymous said...

Thank you so much for this. It seems a shame to spend so much of our town's slender resources on picking up leaves and piling them up where they can do no good at all. For some, leaf removal activities are a kind of seasonal recreation, a hobby or a compulsion and although I personally admire and appreciate the appearance of fallen leaves, each tree with its puddle of pretty leaves below, it is obvious that I am a part of a minority. I do not mean to scold those who take enjoyment in this activity. But while it may be relatively harmless fun and considerable exercise as well, I am pleased to hear "the flip side" of leaf removal. Piling up leaves makes them last a long time. Allowing the elements, wind, rain and sun to scatter and deteriorate them naturally seems both more decorative and much less costly!

Fang said...

Or...if you are going to rake, which is acceptable (and good exercise), at least pile them up, play in them, and then let them compost in a corner. take the compost and spread it on yr lawn in the spring. let's stop fighting the natural systems. more anti-lawn propaganda to come...

Anonymous said...

Unfortunately, some of us live in a neighborhood where rakes have been replaced by the "leaf blower". The noise, in an already congested and highly trafficked environment, is a continuation of the summertime mower cacaphony. Like another reader, I enjoy seeing leaves scattered on the ground, at least for the first few weeks after they fall. Why the obsession with disposing of them so hurriedly?

I do, however, realize that unshredded leaves are not good for the garden, and wish I had a mulcher. Unfortunately, these machines are also very noisy...

Does anyone know how long they take to break down in a compost pile? We have so many leaves that our compost piles can not accommodate them all.

Anonymous said...

This site has some sensible leaf ideas!

Jane Harris said...

While I am a huge advocate of recycling leaves into copost, I understand that many people cannot dispose of their leaves other than by city collection. The good news is that the city delivers the leaves to Millane's Nursery, which does compost the leaves for their growing fields.
Leaf decomposition varies with the species of tree; oak leaves can take a couple of years to break down if left unshreddded.