Controlling Weeds By Design
Defeat unwanted plants in your landscape by planning ahead.
A spark of warm weather and everything’s growing great guns in the garden. And that includes the weeds. Time to get down on our knees and start pulling the plants in our vegetable gardens and flower beds that don’t belong.
If only we’d planned to control them from the start.
Attacking weeds at ground level by pulling them is often the organic gardener’s last line of defense. Though we’re doused in advertisements this time of year showing us how easy it is to spray a dangerous herbicide — they don’t tell us about the dangerous part — that will rid our lawns of dandelions and otherwise kill the green invaders in our landscapes, spraying just isn’t our thing. Using chemicals isn’t the organic way. Besides risking our family’s health and the well-being of our environment, especially our water supply, it’s not all that effective as anyone who has sprayed and sprayed again can tell you.
Then again, pulling weeds isn’t all that effective either. Leave a bit of root in the ground and the plant comes back. And what about all those seeds left behind to germinate?
The best way to fight weeds is to start at the beginning. When you design your landscape, plan it in such a way that weeds will find it impossible to grow.
The The Gardener’s Guide To Common-Sense Pest Control, as far as we’re concerned the Bible of chemical free gardening, is particularly category-minded when addressing weed control. They talk about “indirect suppression” — controlling weeds through landscape design, habitat modification and horticultural controls — and “direct suprression” — killing weeds by pulling them, spraying them, or putting them to the torch. The more effective category, in their (and our) opinion? Indirect suppression.
Take a problem like dealing with weeds that cluster along your fences or borders between flower beds and lawns. The solution is to create a “mow strip.” This is an area along the fence row or between the grass and the garden bed that is covered by brick, concrete or heavy mulch such as wood chips. It not only discourages weeds from growing there, it allows a space for mower wheels so that the mower blades can clip a close edge.
To assure that weeds won’t grow through the cracks between pavers or come up through the bark or wood chip mulch, lay down a barrier between the fence posts or in the space where you’ll set down the pavers. The Gardener’s Guide To Common-Sense Pest Control — where we’ve harvested many of these ideas — suggests using weed block instead of plastic. It’s easier to handle, as anyone who’s worked with black plastic knows, and less likely to puncture or otherwise shred. You can use gravel, sand or garden pegs to hold the barrier down before placing the pavers. Or you can just cover with beauty bark or pea-sized gravel (though be careful when going over it with a power mower; a reel mower won’t throw the gravel into the yard or against your legs).
What about the spaces between large pavers you might use in your walk way or other paths that provide access to places in your landscape for planting, watering, pruning, and the like? Mulch, when spread on a path, will usually be compacted enough by foot traffic to prevent weeds from sprouting. If you pathway isn’t used all that much, consider laying down weed block first. Deep layers of wood chips and beauty bark can provide unstable footing. Pine needles can be used if you have an abundance of them. Just remember that they’ll affect the acid content of your soil. They’re good for acid-loving plants like azaleas and rhododendrons.
If there’s little or no foot traffic expected, then plant to crowd out weeds by planting ground covers. Low growing annual flowers that tolerate some shade, like alyssum or impatiens, will help keep out weeds between larger, showier plants. And they provide their own color. Plan to over-sow when planting, or if transplanting, crowd them closely. Not only does crowding help push out weeds, it will keep the annuals from growing too tall.
In the vegetable garden, consider growing everything in raised beds with sod, gravel, or bark pathways between. The walkways can be further made weed-proof by first laying down plastic or roofing paper. If your garden demands are too much for a few raised beds, then consider dividing your space into sections with permanent walkways. These sections make it easy to plan for crop rotation. And the section can be further divided as necessary by paths between rows or squares that are mulched with clean straw (no seeds) grass clippings and the like.
I have a friend who has divided his somewhat circular garden space with spiraling permanent paths. At the center is his small tool shed. Now it might have been better to have put that shed off to one side, close to his apple trees, rather than in the sun-soaked center of his garden. But the paths twisting away from the entrance to the shed make for something of a web effect.
Children love to run these paths, between the permanent bed of asparagus and the trailing tomatillo vines. Many of his plantings are variations of the square-foot gardening method, though not square. He’s big on companion planting and the science of allelopathy, so his garden is dotted with blossoms. He likes to plant in hills and patches, he practices succession planting, and tends to crowd his plants to the point you’d think it discourages vigorous growth. But he always gets crops. It’s a beautiful, unconventional space that’s most weed free. Just the way he planned it.