The wisdom of weedsJun 23, 2023 02:00PM ● By Bryan Reed
Growing up, I was told that dandelions were weeds and they don’t belong in the yard.
But after reading Katrina Blair’s “The Wild Wisdom of Weeds,” I now embrace dandelions and let them grow where they will. I even utilize them in salads and home remedies.
Blair’s book spells out all the valuable uses of certain weeds, including their nutritional value and ability to heal wounds and abscesses. Many weeds also add organic matter and food for beneficial microbes in the soil, and anchor the soil to combat erosion.
WEEDING OUT THE BAD
Now that I’ve come to understand these misplaced plants, I am selective about which kinds stay on my property. Some weeds are invasive and problematic, so I actively remove them from my garden.
Weeds are extremely adaptable to their surroundings. Think of the tamarisk that thrives along the Colorado River on the other side of the world from its native habitat in China.
Dandelions gravitate to soils low in calcium. They set down a tap root up to three feet deep and pull calcium up from the subsoil into the leaves so that when those leaves die back, the calcium is available for next year’s crop. From that vantage point, when we see dandelions this year, we’ll see calcium next year.
Broadleaf weeds seek soils where the available potassium exceeds the available phosphorus. Increasing the ratio of phosphorus to potassium will result in a definite reduction in broadleaf weeds. Or, when you see a broadleaf weed in your garden, you know that’s a great spot for root crops that crave potassium.
Other weeds that attract themselves to high potassium soils are stinging nettles, kochia and bindweed. Mustard and plantain grow where there’s sulfur available. Wild lettuce indicates a soil high in magnesium and zinc, while comfrey and horsetail fern mine silica out of the soil. For a person seeking to create mineral-rich compost, these weeds would all be good additions, as they accumulate minerals in their leaves and stalks that are released when they decompose.
WEED CONTROL THAT WORKS
There are several sustainable ways to control weeds.
Mulch is a game changer for both weed suppression and moisture retention in the soil. Cardboard overlapped eight inches or newspaper that’s at least four sheets thick can suppress weeds and add organic matter to the soil. Straw and leaves do the same, though I prefer straw as it stays in place far better than leaves.
Plastic mulch has become popular on vegetable production farms. Black plastic suppresses weed growth and lowers the soil temperature by shading it from the sun’s rays. White plastic reflects light up under large canopy crops such as tomatoes and okra. Red plastic increases tomato yields, blue plastic increases pollination in melons and cucumbers, and silver plastic has been documented to lower thrips populations on crops.
DITCH THE WEED WHACKER (WELL, ALMOST)
Flame weeding is an extremely effective non-chemical weed control. It used to be the most popular form of field weeding in the U.S. until chemical herbicides entered the market in the 1940s. I find this method to be kind of fun, so I don’t dread doing it. Plus, it’s gratifying to see all the crinkled leaves and brown, dead weeds the next day.
Any weed burner will work. I used a three-gallon backpack tank on the farms I managed. Walking at a slow pace with a low flame burns the growth points of plants and confuses them. It also doesn’t use much propane.
If you’re flaming weeds in your garden, shield your crops by placing a snow shovel at the base of the plant.
When weed whacking, weeds come back stronger in just three to five days. When you weedwhack bindweed, wild lettuce and plantain, you’re actually pruning it back and forcing the plant to grow two new sprouts where there was only one. Each successive weed whacking doubles the grow back.
With flame weeding, you’re cooking the tips of the leaves where the growth hormones are and destroying the leaf tissue so that a new shoot must form at the roots and push up through the soil. This can take up to three weeks or more which is far more effective than weekly weed whacking.
Spraying pure vinegar on weeds is also very effective and is a much better alternative to chemical herbicides. Make sure to use 30% vinegar (acetic acid), which can be purchased from most garden centers and hardware stores. The standard grocery store vinegar is only 5-6% and won’t work on weeds.
Pure vinegar is also a main ingredient in naturally derived herbicide products, such as AllDown and Phydura.
The most cost-effective way to use vinegar to control your weeds is to take down a majority of the weed biomass with a weed whacker or mower, then spray the vinegar on the remaining plant leaves and crown. It’s best to do it in the heat of the day when the sun is directly overhead. I do recommend wearing gloves when pouring the vinegar solution in a sprayer, as it can cause a rash on sensitive skin. And watch the wind; you don’t want to have the overspray harm the plants you want to keep happy!
Send your gardening questions to Bryan in care of the BEACON, or email him at [email protected]