How do I get rid of crabgrass in the garden? —Sally Heward, Ovid, ID
Crabgrass is an annual weed that comes back from seeds each year. To prevent seeds from sprouting, mulch the soil to prevent light from reaching them. If weed seeds do sprout, they’re easy to pull out of mulch. Or use a hoe with a sharp, flat edge to slice them off at the base.
You can also apply pre-emergence herbicide about two weeks before you anticipate crabgrass germination. However, these products don’t discriminate between weed seeds and desirable plant seeds you’ve sown. Before you apply the herbicide, wait until the seeds you planted have germinated and grown into seedlings with two sets of “true” leaves. A few seeds are exceptions, though, so read the label carefully. (Pre-emergence herbicides are available as both synthetic products and organic products, which are made of corn gluten meal.)
Don’t give up on weed control later in the season. Hoe out crabgrass and other weeds before they flower. Because seeds have fallen for years, and they’ll remain viable for many years to come, new weeds will still pop up each spring. If you stay on top of weeding chores, though, at least the situation won’t worsen