Thursday, January 10, 2013

Gather Leaves While Ye May

Leaves are beginning to turn, and soon they will fall.  Let them lie where they can do what they are supposed to do: feed the soil.  Clean them up off the places where they cause problems: roofs; gutters; pavements; paths; and lawns.  Spread them where they can do good, on soil.  As a last resort, send them to the composter. 
 Leaves will stop most small seeds from sprouting by keeping the sun off them; a couple inches of leaves will smother most small weeds as well.  Leaves will also suppress small garden plants.  You won’t get many pansy volunteers among oak leaves, and too many leaves can even smother the plants.    
To build good garden soil cheaply, pile your leaves a foot deep, well-watered and stomped down, and cover them with an inch or so of compost; this is the equivalent of 6” of good compost; both will grow big vegetables.  Softer leaves are better for this; sycamore in particular will not readily break down when piled, even under compost, unless they are first chopped up in a shredder or leaf vacuum.  Tough leaves like sycamore and magnolia are brittle and bust up into little bits going through the machine.
In my work, I use leaves as base mulch only if they are on site and readily available; otherwise I use straight compost, from 2” for flowers and shrubs to 6” thick for vegetables, and cover it with light top mulch.
Compost, whether piled thick or spread thin on leaves, will dry quickly in the sun and must be covered with a light mulch of bark, wood chunks, or evergreen needles, just enough to hide it from the sun.  Dark, half-composted wood mulch has been my favorite for a while, but only one composter makes it and the supply is not dependable.  Chipped tree trimmings can be acquired through tree-trimming outfits, who keep a list of nearby places to dump them.  Shredded and nugget bark is readily available from landscape supply places; avoid fine or un-sifted bark, as excessive bark dust kills soil organisms with its natural preservatives.  Pine needles are free and renew their supply every year; their downside is a tendency to poke fingers and slide off beds, and they are difficult to spread neatly among plants.
Paths may need mulch of their own; wood chips, shredded and nugget bark, or pine needles work well.  Wood chips are most effective at suppressing weeds; nugget bark lasts longest; shredded bark clings best to slopes.  Pine needles are free and renew themselves.
Leaves are messy, and have a tendency to spread and blow.  Edging your beds with rocks can contain the leaves and give a finished, permanent look to your beds.  Choose rocks at least the size of a football; anything smaller is too delicate to stay in place or hold anything.  They should have flat bottoms and be laid end-to-end, sloping back, for stability.

Published at under The Natural Gardener #6.


  1. This year, 2012-2013, I am picking up bags of leaves from curbs and using them on mine and my customers' gardens. I'm piling soft leaves deep in beds that need more nutrition, and even as base mulch in new renovation. I am spreading hard leaves like oak, sweet gum, and sycamore not very thick on areas that need better annual weed control. Truly, there is nothing as good as leaves for weed control and feeding soil.

  2. I have also settled on a new path material: 4 x 8 sand, a small gravel 1/4-1/8 inch, spread 1 inch thick on flat dirt.

    This is easy to keep free of weeds with a hula hoe (scuffle hoe) and a rake; it cuts the young plants off at soil level, below the crown, which grows at the top of the gravel. Cutting most any young plant below the crown will kill it.

    Particles like gravel tend to sort themselves by size as they are disturbed by rake and hoe; smaller stuff sinks and larger stuff rises to the surface. Dirt clods eventually break up into small particles and join the dirt at the bottom of the gravel, so it stays clean on top. Eventually, worms will work some gravel into the soil and it will need more gravel.