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Winning the war on weeds

RALPH Waldo Emerson wrote in 1878: "What is a weed? A plant whose virtues have not yet been discovered."

I think Emerson was right; many plants that are considered weeds by some people are things of beauty to other people. It's all a matter of perspective, and perhaps tolerance. One of my neighbours enjoys the exuberance of dandelions and grows them on his boulevard, much to the dismay of other neighbours who would like him to conform to accepted norms of gardening.

Weeding is one of the most time-consuming gardening chores but it doesn't have to be. My garden sprawls around my yard and I have a tiny patch of lawn, a driveway, a stone patio or two and the rest of the yard is planted with trees, shrubs and perennials. I spend less than six hours a year weeding. Weeding is not gardening, it's work and I would rather build the conditions that prevent weed growth instead of spending time weeding. What is the key to effective weed control? Simple, plan ahead, choose the right plant for the right place and most importantly - use multiple methods to control weeds. Now that the lie of cosmetic pesticides has been exposed and we know them to be toxic poisons that damage environmental and human health, everyone will have to adapt to controlling weeds without herbicides. It may sound impossible to some people but I assure you that weed control, not eradication, is possible.

Mulch is the first line of defense in controlling weeds in the garden. Without mulch you can never win the war on weeds. Along with all of the other benefits that mulch provides, mulch prevents the germination of weed seeds by burying the seeds and preventing sunlight from facilitating seed germination. And if weeds do manage to get a foothold in the mulch they are easy to pull out because they grow in the mulch before they reach the soil. If you don't agree with the reality of mulching to prevent weed growth then by all means, continue weeding your garden by hand or pay someone to cultivate your fluffy black soil to prevent weed growth. But you will never win the war on weeds. Weeds are adapted to produce an abundant amount of seeds to rapidly colonize almost any bare soil. Weed seeds can last for decades in the soil and still germinate once they receive light or water. Weed seeds are also adapted to spread by wind, water, and as cling-ons on people or animals. Weeds grow above-ground flowering structures to spread their seed and many weeds spread underground to colonize. Weeds have been growing and learning for a million years to adapt and survive. Humans have only been growing the "gardens of suburbia" for a mere 50 years or so. And there

are billions of weeds.

For those of you who do mulch but prefer to install landscape fabric underneath the mulch as an extra line of defense, don't waste your money. Landscape fabric is effective in very few situations such as in nurseries and for erosion control, but in the residential garden the fabric is less effective and for my money useless and a long-term interference when changing the planting is required. The main limitations of the fabric are that seams, edges or plant holes grow weeds and the fabric impedes air and water movement through soil, which suppresses plant health.

Vigorous weeds that spread underground such as horsetail and morning glory must be dug by hand. There simply is no other effective way to get rid of them. You can spray, hand pull or lasagna-mulch those weeds but you will not kill them, they simply sit and wait for another opportunity to grow. I prefer to use a small excavator to dig out those weeds, it's effective, easy and there is no concern that you missed some.

Planting your plants close together, called closecropping which is a form of permaculture, will allow the plants to grow a mosaic of colour and texture across the garden while suppressing weed growth.

Combining close-cropping with a robust mulching program is the most effective way to prevent weed growth. If the weeds make it through the mulch they still have to grow through the plant canopy to get at sunlight, which rarely happens.

Preventing weeds from growing or entering your property, known as exclusion, is also a very effective weed control method, but few people take the time to get that one weed before it spreads seed across the garden. Procrastination is the friend of weeds.

Janice Maeditere once said: "Weeds are nature's graffiti." We have a lot of nature's graffiti. And like graffiti, weed growth never ends. So be smart and design the garden to withstand the weed's wrath.

Todd Major is a journeyman horticulturist, garden designer, writer, consultant and organic horticulture teacher. For advice contact him at stmajor@shaw. ca