Hill Gardens of Maine -- Successful Vegetable Gardening, Part 3

Answers to your gardening questions

Five-part article series on flower-drying starts here

Eight-part article series on vegetable gardening starts here

Asian Lily Beetles

A new scourge in New England ornamental and veggie gardens.

Japanese Beetles

They can be controlled...but not the way you think.

An effective Deer Fence!

Only three feet tall...and no deer has ever jumped over it!

The Success-Oriented Vegetable Gardener, Part 3—Mulches, Green Manures, & Cover Crops
by Fred Davis, MG, Hill Gardens of Maine (To view previous articles, click: Archives)

Welcome through Fred's Garden Gate! All three of the subjects in this weeks' column have been covered in the past but I firmly believe that repetition is the best form of learning. So let's take another "refresher" look to see just how mulches, green manures and cover crops will help us to become more successful vegetable gardeners.

Mulches. Reasons for applying mulches are almost legion, but they can be cooked down to these few: as a protection against the icy winds of winter and the heaving of spring; to prevent evaporation of moisture, thereby conserving ever more valuable water; protection of the soil surface from erosion by wind and rain; inhibiting the growth of unwanted seedlings - especially weeds; and for the prevention of various soil-borne plant diseases.

Mulches come in different forms, suited to several vegetable garden uses. Wood and bark chips, for example are excellent for long-term surface protection and weed suppression. Compost (decayed plant material) also adds valuable humus to soils plus it suppresses certain diseases and, because of its near-neutral pH, helps to repel even the most determined slugs and snails.

Inorganic (or manufactured) mulches have long been used by gardeners and small farmers, and their value is unquestionably established. Clear poly film, for example, warms the soil, sometimes to the point of destroying weed seeds, plant diseases and harmful insects. Black (opaque) poly is commonly utilized as a cover over large areas of vegetable gardens to suppress weeds, conserve moisture and maintain soil temperature. Indeed, combining black (or other infra-red blocking) material with increasingly-popular floating row cover (REEMAY) has been shown to double the yield of many vegetable crops - and earlier, to boot!

Green Manures. Even though you might consider the compost or aged manure which you apply in the spring to be more than ample, there is always room for more! A green manure is a crop of some type of plant which, instead of being harvested to feed us or our animals, is chopped up and entirely returned to the soil - just at its prime.

Green manures abound in organic matter, contain significant amounts of nitrogen ("food" for plants...and the soil micro-organisms which cause it to break down into rich, dark brown humus) and, over the long haul, improves soil structure and vitality. You get better, bigger, tastier vegetables and, in the bargain, buy a natural "insurance" policy against deterioration or destruction of our most valuable natural resource - soil.

Hand-in-Hand. Green manures and cover crops are almost literally the same thing. Cover crops, like green manures, are plants seeded for a particular purpose - not necessarily for human or animal consumption. Both are returned to the earth to improve soil structure and tilth; each contains nitrogen (and other elements essential to plant growth and health); both are seeded in soil left bare by recent harvests; in a way, each could rightly be considered a living mulch.

The difference is one of timing. Green manures are often planted early in the season and, because they're fast-growing, can be tilled in just before maturing - a week or two ahead of planting the vegetable crop. Some gardeners accomplish the same purpose by collecting and shredding early weed growth (before it sets seeds!), spreading the ground-up greenery on their garden, and plowing or rototilling it in. Either way, you get essentially the same effect: added organic matter, improved soil structure, better moisture retention and much happier crops.

Practically any low-growing plant, particularly non-invasive ground covers, can be utilized as living mulches. Space them so they'll just touch when mature. Some gardeners prefer one of the annual rye grasses, or white or yellow clover. Ajuga and vetch make an effective living mulch but can become invasive.

Cover crops are also seeded into soil left bare by human activities. The smart gardener immediately seeds a cover crop (which could be considered green manure) the very day that crops are harvested. Not a moment to lose! Take advantage of every precious second of growing time! "Cover" up bare soil with plants. Rather than take nutrition from the ground, air and water, and waste it, cover crops, which are later tilled in, store all that plant "food" to be used another day (or season). Buckwheat, winter rye and white clover are appropriate cover crops.

Cover crops are also a must for protecting garden (or farm) soil from the ravages of winter: rain, wind and flood. Thick roots and a layer of surface organic matter bind soil particles, preventing them from washing or blowing away.

There's really no question about it...mulching, cover-cropping and green-manures are three of the most effective strategies for insuring continued success in your vegetable garden - and flower garden, too.

Seed (in bulk) for this proven method of protecting your soil is readily available from places like Agway, Johnny's in Winslow, Maine (http://johnnyseeds.com), or one of many other large farm and garden suppliers in your area.

Next time we'll kick around as many "secrets" of successful gardeners as we have space for.

Jump to Veggies Part 4 Hints, Kinks & "Secrets"

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