Q: I've Just Sprayed With Selective Broadleaf Weed Killer And Now The Dandelions Are Bigger Than Ever! What's Up With That?
The principal active ingredient in many broadleaf weed killers is 2,4-D, an artificial form of a natural plant growth hormone. When 2,4-D first goes to work, it often stimulates vigorous leaf growth and causes the plant to bloom lavishly, making it look healthier than ever. But internally, the treated dandelion is growing itself to death. The weed will soon begin to wilt and be dead from top to bottom in a few weeks.
Q: I've Heard That Southern Lawns Can Be Sensitive To The Ingredients In Some Broadleafe Weed Killers. Is That True?
Yes, many warm-season grasses are more sensitive than cool-season species to lawn weed killers of all kinds. But that doesn't mean you can't use many of them on southern lawns. You simply need to mix the product correctly. In general, they should be mixed at reduced concentrations for warm-season grasses. Two exceptions are worth noting, however:
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Concentrate should be mixed at the northern lawn rate for use on Zoysia grass.
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Products should not be applied on the Floratam variety of St. Augustine grass unless specifically recommended. Most can be safely used on other varieties of St. Augustine.
Q: Can I Spot Treat Late-Sprouting Weeds After I've Treated The Full Lawn?
Yes. Though you should limit full-lawn application of lawn weed killer to twice a year, it's fine to spot treat any weeds that survive the initial treatment (or crop up later) with ready-to-use spray or properly diluted concentrate. In fact, spot treating weeds whenever they appear is a great way to stay on top of them.
Q: Can I Use Broadleaf Weed Killer For Lawns To Control Crabgrass?
No. Weed Stop is formulated to kill broadleaf weeds like dandelions, dock, velvetleaf and poison ivy. Crabgrass -- and other grassy, narrowleaf weeds such as goose grass -- should be treated separately with products made specifically to control grassy weeds.