A year-round blanket of organic mulch material makes for an almost labor-free garden.
Year-Round Organic Mulch
My affair with organic mulch began nearly 15 years ago, when I
picked up an intriguing (and now classic) gardening guide
about love at first sight! Ever since I was a boy, I’d
enjoyed gardening–but I’d hated hoeing and weeding.
So when I opened the book to the first chapter and read the
title, “Throw Away Your Spade and Hoe,” I knew I’d found
something worth trying.
For the next several years, I followed my new mentor’s
advice, covering the garden with a deep blanket of organic
mulch material to smother weeds, help the soil retain moisture
and virtually eliminate the need to till, plow or hoe.
Vegetables thrived amidst the nurturing mulch, protected
from temperature extremes and fertilized by the decomposing
straw or leaves.
But of course no good gardener stops searching for ways to
improve. I became interested in biodynamic/French intensive
(BFI) gardening, which involves growing plants in permanent
raised beds that have been double-dug to a depth of two
feet or more. Because of the deeply loosened,
compost-enriched soil, plants can be spaced closer
together, resulting in dramatically increased yields. I
liked being able to raise more food in less space, but
there was a lot of labor involved in double-digging.
Furthermore, I found making and hauling compost–which
BFI practitioners apply to their beds liberally and
often–to be hard work. Finally, BFI gardeners tend to
shun mulch, preferring instead the “living mulch” created
by the overlapping foliage of closely spaced plants.
Experiment, Adopt, Adapt the Garden
If I’d learned anything from experience and from Ruth
Stout’s books, it was to experiment . . . to try different methods, to be open to the
ideas of others, but always to temper those ideas with
common sense. What works for another gardener may not suit
your particular gardening conditions; sometimes it’s
necessary to adapt deep-mulch methods to your own
situation.
“Gardening is like cooking: Read the recipe and then use
your head,” Stout wrote in her landmark book about
low-labor growing, How to Have a Green Thumb Without an
Aching Back. “A dash of skepticism can do no harm. Go
lightly on caution, heavily on adventure, and see what
comes out. If you make a mistake, what of it? That is one
way to learn, and tomorrow is another day.”
Applying that principle, over the years I’ve blended
components of BFI, mulch and conventional gardening
techniques into a system that works for me, and that (here
in USDA Zone 5, at least) seems to allow its various
elements to complement one another. The result is a hybrid:
a no-till, permanent-raised-bed, deep-mulch garden system
that provides several key benefits over other methods I’ve
tried:
- Raised beds provide superior drainage in wet weather,
allowing a garden to be deeply mulched without keeping the
soil too wet for too long. Raised beds also help you
produce noticeably larger yields in less space, and
(because you walk only between beds, never on them) they
prevent soil compaction from foot traffic.
- Deep mulch
virtually eliminates weeding and hoeing, fertilizes plants,
prevents soil compaction (and muddy gardening conditions)
due to rain, creates a fertilizing humus, improves tilth
and encourages a thriving population of worms, beneficial
bacteria and fungi.
- The combination of dense planting and
deep mulch provides a double layer of mulch–both
living foliage and dead organic material–that
protects the soil far better than either of the two methods
would alone.
- Because it requires so much less labor, a
mulched garden makes gardening possible and fun even for
small children (kids love to spread mulch) and for senior
citizens and handicapped people. For the same reason, you
can leave a mulched garden for two or three weeks–to
go on vacation, for example–and not come back to a
jungle of weeds. During the busy harvest season, you can
concentrate on picking, preparing and preserving your
vegetables rather than on hoeing and weeding.
Garden Bed Preparation
You don’t have to double-dig to make a raised bed;
you can single-dig, plow or rototill the ground. (Keep in
mind, though, that every time you till you destroy worms.)
The important thing is to produce a mound of loosened soil
three to five inches deep and three to four feet wide; the
length and shape of the bed are entirely up to you. You
also have a choice of many methods for holding the soil in
the beds. Some gardeners build borders from planks staked
or nailed into place, while others use landscape ties,
fieldstones, bricks or cement blocks. Most of my beds are
simply heaped earth with the sides sloped at a 45 degree
angle. Mulch prevents the beds from eroding away. (This
method works fine in clay or loam soils but probably
wouldn’t be effective in sandy soils.)
When I start beds from scratch in sod, I rototill the area
several times over a two- or three-month period to kill the
grasses. (Quack grass, however, is so persistent that I dig
it out by hand; rototilling a single clump chops it into
hundreds of pieces that become hundreds of plants.) Then I
simply heap top-soil from around the bed–in other
words, from the aisles–to form the bed itself. I make
most paths between the beds 15 inches wide, and main aisles
wheelbarrow width.
Once I’ve dug and formed a bed, I’ll never dig or till it
again, so at this point I work compost or other amendments
into the area. This is an especially good idea in heavy
clay or sandy soils.
Planting the Garden
You plant a raised-bed mulch garden just as you would
any raised-bed garden: Place the seeds close
enough so that, when the plants are mature, their leaves
will overlap to form a continuous canopy. If it’s a new,
unmulched bed, sow the seeds as you normally would. Make a
furrow (or hole, or whatever is appropriate) in the ground,
plant the seeds and cover them with soil. Then sprinkle a
little well-rotted mulch or compost on top of the earth to
prevent soil crusting, and place mulch on either side of
the planted area to limit weed growth and compaction from
rain. As the plants grow, tuck mulch around them.
If the garden is already mulched, it’s an easy task to move
the thin (one- to two-inch) layer remaining in spring and
plant. For example, to plant peas I rake the mulch back to
form a one-foot-wide strip of bare earth. Then I plant just
as I do in unmulched beds. With finer seeds such as lettuce
or carrots, I’ll rake of an area about four feet square,
sprinkle the seeds directly on the ground and cover them
with a bit of compost or rotted mulch. This is as close to
planting the way Mother Nature does as any method I know.
What Organic Mulch?
You can use newspapers or plastic sheeting as mulch, but
they add little (in the case of newspaper, which decomposes
slowly) or nothing (in the case of plastic) to the soil . .
. and they leave a lot to be desired aesthetically.
Newspapers do work well for mulching aisles, though. I take
care not to use colored newspapers, however (harmful
chemicals can leach into the soil), and I cover the papers
with hay to hide them and to keep them from blowing away.
I prefer organic mulches, which not only fertilize the soil
but feed my plow jockeys (worms). Hay and straw are
excellent and long-lasting Grass clippings are good but
decay more quickly. Be careful not to use clippings from
lawns that have been treated with weed killers; traces of
herbicides can be deadly to tomatoes (although, in my
experience, they don’t seem to harm fruit trees and some
other garden plants). Bark chips make an attractive mulch.
Leaves are fine, too, but only if they’ve been shredded or
composted for a year. Freshly raked tree leaves cake
together and smother the soil, retarding plant growth
(raspberries, however, thrive in such material). Finely
chipped tree limbs make a good, enduring mulch (but let the
chips age and soften a year before you try to walk in your
garden barefoot).
I’ve heard people say that sawdust and some other organic
mulches pull the nitrogen out of the soil; as far as I can
tell, this is true only at the surface and doesn’t extend
into the earth. I’ve never noticed such a problem in all my
years of mulching.
There are many kinds of other materials you can use for
mulch: corncobs, cocoa shells, rice hulls, etc.
Availability is probably the most important consideration;
the best choice is usually whatever is easiest to find and
least expensive. A good bale of hay can cost $2 or more,
although some farmers will give spoiled hay away. Wood
chips from a nursery can be pricey, but tree trimmers will
sometimes deliver chips to your garden for free.
Just keep an eye out for prospects; you’ll be surprised at
how much material is out there.
When to Mulch the Garden
Anytime is the right time to start mulching. Here
in Illinois, I keep a comparatively thin (two-inch) layer
of mulch on my garden most of the year, because in this
climate a thicker mulch during cool seasons would chill
heat-loving plants. Sometimes I rake the mulch off a vacant
bed in order to plant, or to let the soil warm up for a few
weeks before planting (though my thin mulch seldom retards
soil warm-up significantly). I don’t mulch my garden deeply
until the weather gets hot and dry. Then I really pile it
on: up to eight inches if I can. Obviously, with short
plants such as lettuce this is difficult, but with
potatoes, broccoli and other tall cultivars it’s easy to
do, and the plants love it.
I also adjust my mulching to suit the particular plant. For
example, broccoli prefers cool soil, so I pile mulch on my
broccoli beds early in the season. Tomatoes like it hot, so
I don’t mulch them heavily until summer starts to hit
hard–usually June but sometimes as late as July. Of
course, I also throw mulch on any spots where the layer is
thinning out, or where weeds start popping up.
As the season progresses into fall and the weather cools, I
no longer need to add mulch–which is convenient,
since I need the time for harvesting and preserving my
garden’s bounty. If I notice a patch of bare soil, I’ll put
a little mulch on it, and if a bed seems particularly wet,
I might pull a little of the material off.
By the following spring the mulch, having settled and
decomposed, is no more than a couple of inches thick, but
that’s enough to prevent soil gusting and to discourage
early weeds. There’s no need to till or plow
organic mulch conditioned soil, so I don’t have to wait several
weeks–as most gardeners do–for the garden to
dry enough to tolerate tines or a plow blade. I plant peas,
lettuce and other cool-loving crops as soon as the ground
thaws in the weak sunlight of early spring.
The Great Moderator
There is no single right depth for mulch, no more than
there is a single best material to use or a perfect time to
use it. You can add mulch or take it away, apply a thin
layer or heap it on thick. More than just a way for lazy
gardeners to avoid tilling and weeding, mulch is a great
moderator–you can use it to adjust soil moisture and
temperature, to protect against frost and drought, to
create just the right conditions for a particular type of
vegetable or flower.
If you try some of my mulching techniques (or Ruth Stout’s,
or anyone’s) and they don’t quite work, don’t dismiss the
method altogether. Instead, see if you can find out how to
change the way you use mulch to suit your own situation.
For example, if mulch seems to keep your soil too moist for
too long, perhaps you’re applying too much too early. If
you garden in sandy soil, a conventional flat row garden
may be a better idea than raised beds. If insects become a
problem in your mulched garden, the kind of mulch
you’re using could be to blame–or (even more likely)
perhaps the cause is entirely unrelated to mulch.
[Editor’s Note: Some type of mulch are used to
fight pests. A deep mulch of leaves, straw or hay
discourages potato and cucumber beetles; sharp sand repels
slugs.]
I think the advantages of using mulch–not the least
of which are less labor, a longer season, more control over
soil conditions and a garden that improves year after
year–are well worth a little trial and error.
RECOMMENDED READING
Books by Ruth Stout:
The Ruth Stout No-Work Garden Book (Rodale, $9.95).
Gardening Without Work (Cornerstone, $1.95).
How to Have a Green Thumb Without an Aching Back
(Exposition, $7.50).
Other Useful Books:
No-Dig, No-Weed Gardening by Raymond Poincelot (Rodale,
$10.95).
Jeff Ball’s 60-Minute Garden by Jeff’ Ball (Rodale,
$9.95).