How to Control Garden Weeds
Hoe, mulch or a touch of herbicide
The better you control weeds in the garden this year, the fewer weeds you will have next year. Weeds have the capacity of generating thousands of seeds, which means that many seeds scattered on the ground this year will be germinating next year. Not all of the seeds will germinate at once. Many hard seeds can remain in the ground for years, especially if they get buried.
Frequent light cultivation while the weed seedlings are small is the best method of control — providing you have the time.
When cultivating or hoeing, disturb as little soil as possible. The more soil you disturb, the more weed seeds you are likely to stimulate into germination. Most of the weeds in hiding are summer annuals that require being exposed to sunlight to germinate. With ample moisture in the soil, many need only a second or so of light to initiate germination. Many large commercial farms now sow and cultivate their crops at night to minimize weed problems.
I use a hand-push, single-wheel cultivator with a sharp, flat Nebraska blade that slices the weeds at the soil line. This tool causes little disturbance of the soil, and it can be used with minimum effort. The Weed Bandit is also a good tool for controlling weeds.
Whatever your tool, it must be sharp. For good weed control when seedlings are young, all that is necessary is to cut the top from its roots. The roots are not capable of regenerating at this stage of development. You can do all you need by simply scratching the surface of the soil. Controlling weeds that are several inches tall requires more effort and more digging.
Mulch can also control weeds. Unless you are using black plastic, mulch tends to make the soil cool. If you are growing tomatoes, peppers or eggplants, delay mulching until the first cluster of fruit is forming. Plastic mulches must be anchored along the edges, lest they blow away. You can mulch with newspaper, but you’ll need 10 to 12 layers to provide adequate weed control. Unless kept wet or anchored, the paper can blow away. Shredded paper or cardboard makes better mulch because both are easily spread and, once wetted down, tend to mesh together and stay put. The other nice thing about using paper is that it will rot in place and leave little residue because it is pure cellulose.
Straw is often used in the garden, especially around tomato and pepper plants. However, unless the straw is free of weeds, it can be a source of more and different kinds of weeds next year. Never use hay as it is generally loaded with seeds.
The only herbicide I feel comfortable using to control weeds is Preen. A fluoride, it is effective only on germinating weed seeds. It has no effect on weeds once they have germinated. It must be applied on clean cultivated soil and watered immediately. I use it in my asparagus bed only after we have finished cutting. I use it in the onion bed two to three weeks after the transplants have been planted. I also use it with carrots, parsnips, radishes and beets after the rows have been thinned to the proper spacing. It is useful in the flower garden applied one to two weeks after transplanting.
To avoid injury, Preen must be applied as directed. It will provide control of crabgrass, goose grass and a few other weeds for six to seven weeks. This is time enough for the crop to shade the ground and the weeds.
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