No Till Gardening
Excerpted from: Till versus no-till gardening
Excerpted from: What is no till gardening or farming?
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While the practice of no-till gardening is not new, information has traditionally centered
on agricultural field crops. Now, home gardeners are catching on.
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Soil tilling causes soil disruption, which compacts the soil and destroys the pathways that
channel air and water through the soil. Every time a tiller cuts through soil the structure is
weakened, which can cause compaction and increase runoff. There’s also erosion and
surface crusting that results from over-tilling.
Tilling disrupts the microorganisms and other soil dwellers that live in the top couple of inches
and are essential for soil and plant health. Soil microbes, some of which have a symbiotic
relationship with plants, cluster around roots and, as they feed on organic matter and each
other, secrete nutrients that feed plants and substances that act as glue to bind soil particles
into larger aggregates that keep soil pores open.
Long strands of fungal hyphae can hold the aggregates together and earthworms and other
large organisms also work to create pore space.
Examples of different types of soil structure: a) blocky, b) columnar, c) massive, d) single grain, e) platy.
No-till gardening, also known as ‘no-dig’ gardening, is the practice of avoiding the intentional
disruption of soil. Rather than using plows, spades, hoes, or other tools to routinely “turn over”
soil, it is more or less left alone.
Many no-till gardeners choose to leave the roots of spent plants in place. At the end of the
growing season, they cut plants out at the soil line (or just below the soil) with pruners or a
small hand saw – rather than yanking out the entire plant and root system.
In the no-till world, instead of mixing amendments deep into the soil, slow-release organic fertilizers,
compost, and/or mulch materials are added to the top of the soil on occasion. Those things, along
with the left-behind plant roots, slowly break down to rejuvenate the soil and provide food for new
plants.
Soil coverage is also an important concept in a no-till system. For home gardeners, this can be
achieved by using cover crops or mulch. Mulching materials may include straw, compost, aged
livestock manure, dried leaves or grass clippings. Mulch will protect the soil from rain and wind,
which can cause erosion. In early spring, the mulch layer can be pulled back from the bed to allow
sunlight to warm the soil.
Here’s how to create a lasagna bed, also called sheet mulching:
Start in fall so the bed has all winter to start decomposing.
Cut grass as low as possible. Or start a lasagna garden on top of an old planting bed.
Loosen soil with a digging fork to increase aeration. Even punching holes in the ground will work.
Remove weeds.
Build a raised bed frame or just mound up the layers of organic material into an unframed bed.
Put a layer of cardboard overlapped an inch or two and water it.
Cover with 2-inch layers of green organic material like grass clippings, fresh plant debris, fresh
animal manure and food scraps that provide nitrogen and brown materials like dry leaves,
wood chips, straw and shredded newspaper that are carbon sources. Repeat layers until the
bed is about 18 inches.
Top off with a 2- to 6-inch brown layer; thicker if you want to plant right away.
Create beds only wide enough to reach into the middle and create paths lined with straw to
walk on so soil doesn’t get compacted.
Add organic inputs to the top of the soil routinely, at least once or twice per year. Great examples
include aged compost, leaf mold or dry leaves, pine needles, fine bark or wood chips, or other
natural mulch materials.
Come planting time, we add worm castings and mycorrhizae in the planting hole around the root ball
of new seedlings. Worm castings are a form of mild slow-release fertilizer that also improves soil
structure.
Mycorrhizae are microscopic fungi that colonize plant roots, and essentially extend the surface
area and function of roots. The symbiotic relationship between mycorrhizae and roots increases the
plants ability to uptake nutrients, water, and more.