You want a beautiful lawn for your family to enjoy, but it's no longer enough to just mow it. You have to fertilize, water, kill weeds and then reseed any bare spots. Using a weed and feed product saved you some time, so now you're ready to plant some grass seed. You may have to wait a bit longer, though, depending on the type of weed and feed product you used.
1. Weed and Feed
Weed and feed products consist of fertilizers such as nitrogen or potassium, and a pre-emergent or post-emergent herbicide. If the weed and feed is designed for spring application, it contains a pre-emergent. If it is designed for later in the growing season, it incorporates a post-emergent herbicide. Knowing which one you are using is important because the herbicides affect plants in significantly different ways.
2. How They Work
Pre-emergent weed and feed is applied in early spring so the herbicide is in place before the undesirable weeds germinate. Pre-emergent herbicide works by inhibiting germination. It must be watered with at least one-half inch of water to move the chemical from the surface into the soil. Post-emergent herbicides, however, must be applied while the weeds are actively growing because for the chemical to work, the herbicide must be absorbed into the plant.
3. Why You Wait
Since weed and feed products are designed to prevent germination -- or to eradicate a living plant -- they can, for the most part, have a similar effect on young turf grass. The only exception is the pre-emergent herbicide siduron, which is actually used to assist in seed germination. When using a pre-emergent that does not contain siduron, wait a minimum of two months before seeding. If using a product designed for broadleaf weeds, read the label carefully, because the active ingredient in these post-emergent herbicides have a wider range for the waiting period. Grass can be planted in as little as one month after application for products using 2,4-D to as much as six months for atrazine-based products.
4. Proper Seeding Methods
When you are ready to seed your lawn, use a garden rake to remove debris and to break up the surface to ensure the seed comes into contact with the soil. Broadcast the seeds in two directions to ensure complete coverage, and water the ground lightly and often for up to two weeks -- keeping the soil moist. Once seedlings have established, gradually reduce the frequency of the watering, but lengthen the amount of time per watering. This will encourage a deep root system for your grass.
- The University of Georgia College of Agricultural and Environmental Sciences: Weed Control in Home Lawns
- University of Wisconsin Extension: Lawn Weed Control
- Colorado State University Extension: Control of Annual Grassy Weeds in Lawns
- Colorado State University Extension: Plant Talk- Seeding a lawn
- Scotts Turf Builder Weed and Feed label
- Scotts Turf Builder Bonus S Southern Weed and Feed label
- Chad Baker/Thomas Northcut/Photodisc/Getty Images