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In the Garden: Weeds useful as mulch or at dinner table

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Getting behind with weeding is surely among the top three gardening problems here on the West Coast. Some people like to smother weeds, while others prefer pulling. Then there the mavericks who strew them on paths or mulch with them… or even eat a few of the tastier ones.

Young dandelion shoots can be used in salads. So can sorrel. When boiled, young stinging nettles make a delicious (non-stinging) substitute for spinach, as do lamb’s quarters (though this cooks down to almost nothing). Chickweed cut small is a fresh-tasting salad green.

But the most earth-friendly weeding tactic is mulching with plant material. It’s especially useful in organic veggie gardens. Natural mulch conserves moisture, earthworms love to breed in it, and left on garden beds through winter, birds forage there endlessly.

Gardeners with lawns find the cheapest, easiest way to get mulch is grass clippings – but hold the clippings back slightly from tiny vegetable seedlings; you can move it closer as they grow.

Since lawns also need nourishment, it’s best to keep grass length at about eight centimetres (3½”) and sprinkle nutriments or compost on lawns in spring or fall. Once the veggie garden doesn’t need any more mulch, the clippings can just remain on the lawn.

Other useful mulches for vegetables include straw – though it’s sometimes seedy. Weed-free compost makes another good mulch. Commercial compost isn’t organic but it’s always weed-free. Home compost is variable. Well composted manure is a good mulch for heavy feeders such as corn or rhubarb.

When weeds get quite out of hand, black plastic can do a great job of smothering them and their seeds. Unfortunately, it tends to break up if left in one place more than a year.

Clear plastic breaks up even faster than black plastic, but it can be used briefly for solarization, as clear plastic magnifies the heat of the sun to oven temperatures, roasting weeds and surface seeds. This weed-clearing method only works when there’s hot temperatures and sunny weather for about six weeks.

Cardboard or newspaper makes a good base for a garden bed of mounded soil and compost. Ultimately, both rot, so deep-rooted plants can establish themselves well.

Tightly woven landscape fabric makes a good weed barrier under a gravel or paver path for virtually every weed except couch grass (aka quack grass), a perennial grass with  fat white needle-pointed roots that can punch through many landscape fabrics.

If it appears in gravel, it’s much easier to attack from above.

Boiling water kills top growth most effectively, though it should never be used in gardens anywhere near toddlers or pets, or by people with balance problems. Other organic weedkillers are usually based on horticultural vinegar. You may need to douse the offenders several times.

When weeds get past the seedling stage, triage is sometimes necessary. Anything with seedheads, flowers, or buds should be dealt with first. If there’s no time for pulling, at least cut them off so that crops or flowers can get ahead. Pulling is much easier when the soil is moist.