When it comes to taking care of your home and garden, your time is money, too. If you want to spend next spring and summer pulling weeds from your lawn, you’re taking expensive time away from the things you’d really like to do. But weeds are inevitable, you say? They sure are. You might even start with a freshly seeded or sodded lawn, but unless you’re growing that lawn in a glass bubble, weed seeds are going to find their way in… blown by the wind, casually dropped by passing birds, and tracked on your shoes or on the paws of your best canine pal.
The trick is to stop the weeds before they start. If you don’t know when to apply pre-emergent herbicides, the answer is early spring before weeds have a chance to germinate. If you can recall when weeds began appearing this year, count back two or three weeks and that’s the time to apply a pre-emergent next year.
If your memory is foggy — it feels as if you’ve been fighting weeds forever — think of when your crocus or other bulbs began popping up or when the forsythias or dogwood came into bloom, and then count back the two or three weeks from then.
There are also benefits to applying a pre-emergent in the fall when some hardy perennial weeds like dandelions are busy storing up energy and growing deep roots so they can survive the winter and emerge in spring. It’s when the weather starts cooling off that they shift gears from using nutrients in their leaves to using them in their roots, so an herbicide applied at this time of year will be directed downward along with those nutrients. Watch your timing, though, because herbicides are most effective when the air temperature isn’t lower than 50° F.
Here’s a weed primer with some facts you probably didn’t know:
These weeds are the hardest to eradicate because they survive and reproduce even in poor conditions, relying on bulbs, rhizomes, runners, tubers, or thickened storage roots for their survival between seasons. Perennial grassy weeds are the most difficult problem because their species are similar to lawn grass species.
In fact, some varieties of grassy weeds would be considered desirable as turf if they were growing in a contained area and not competing with the type of grass you want for your own lawn. Be careful in choosing the right herbicide for these grassy weeds because spraying with a nonselective herbicide may also kill the kind of grass you’re growing in your lawn.
These weeds can’t survive underground from one year to the next, but some pop up at times of the year when pre-emergent weed killers aren’t active, and can be resistant to post-emergent herbicides.
Hand-pulling them is sometimes all you can do. (It may be an old-fashioned cure but the extra effort is good for your waistline.) Regardless of whether or not you treat them, most annual weeds that survive the summer will die off quickly when temperatures drop in the fall.
Beware of Pretty Weeds
The first step toward controlling weeds is knowing what kind you’ve got growing in your lawn. Some of the most attractive weeds look like wildflowers and you might feel the urge to leave them where they are, but they can do real damage to your lawn if you let them take over.
Dandelions: These are a broadleaf perennial that grow from taproots that can be two to three deep in the ground. They grow charming yellow flowers that mature into the white puffballs full of seeds that spread on the wind and take root wherever they land. You’ve got to dig up or kill their roots or they’ll reappear each year in ever increasing numbers.
White clover: This is another perennial weed with a pretty white, fluffy bloom. It grows from creeping runners that need complete eradication before they choke out your lawn.
Creeping Charlie: A member of the mint family, this is an aromatic perennial with tiny purple flowers. It can form large patches in shady, moist areas of the lawn and is difficult to control. In various areas of the country, this weed is also called ground ivy, cats foot, field balm, and run-away-robin.
Oxalis: This is a broadleaf perennial that can grow to twenty inches high, with cup-shaped yellow flowers and light green leaves that resemble clover. It grows in both sun and shade.
Wild violet: While this lovely perennial with its small purple flowers and heart-shaped leaves is sometimes grown as an ornamental, consider it a weed if it’s growing in your lawn.
For help identifying weeds in your lawn and garden, garden.org has good descriptions and photographs.