How Many Days Do You Have to Wait Before Seeding After Weed & Feed?. Weed and feed fertilizers are often used in combination with seeding. Weed and feed formulations consist of two components: a herbicide to kill weeds and a fertilizer to strengthen the turf. The herbicide will weaken the grass as well as the … Here’s a little known lawn secret: If you have a Bluegrass, Fescue or Ryegrass lawn, your grass roots are still growing in your soil that is warmer than air temperatures. Even if you’ve already fed this fall, another feeding now can really help build your grass roots. So put on your gloves and ear muffs…
How Many Days Do You Have to Wait Before Seeding After Weed & Feed?
Weed and feed fertilizers are often used in combination with seeding. Weed and feed formulations consist of two components: a herbicide to kill weeds and a fertilizer to strengthen the turf. The herbicide will weaken the grass as well as the weeds and the fertilizer will strengthen the weeds as well as the grass. When applying seed over a weed and feed application, remember that some weed and feeds can prevent grass seeds from growing.
Types of Herbicide
It’s important to know a little about herbicides so you can make the best choice for when to apply seed in an area that has been treated for weeds. The most common types of herbicide in weed and feed products are selective and systemic. Selective herbicides target a species of plant to kill while systemic herbicides work by being absorbed though the roots and then transported throughout the plant, killing it from within. Read the bag label to see what kind of herbicide is used in the weed and feed you are considering using or have used. The bag label will tell you how many days you must wait before applying seed to a lawn that has been treated with that product.
Herbicides can target weeds before they germinate from seed – pre-emergent – or as developed plants – post-emergent. Before you seed, you can use a non-selective, post-emergent herbicide to control any weeds in the area to be seeded. Most of these can be applied up to two weeks before seeding to control any existing weeds. Herbicides should not be used after seeding until the new seedlings are established. Mowing and spot treatments can be used to control weeds until the seeded area is actively growing and requires only maintenance watering. Establishment times vary depending on the type of seed you use and your weather conditions.
Using Weed and Feed
Only use a weed and feed if the weed infestation is completely uniform over the entire lawn and all species of weeds targeted will be affected by the herbicide in the weed and feed. This scenario doesn’t occur often, so it is more likely the use of an herbicide and a fertilizer separately will be needed. If the weeds are uniformly spread over the area to be treated, match the appropriate weed and feed product to your grass, the seed you have recently applied or want to apply, and the time of year.
Know What You Grow
It is important to know what kind of grass you have growing or want to have growing. Certain chemicals act differently on different species of grass and weeds. For example, the common herbicide 2,4-D is toxic to some cultivars of St. Augustine grass (Stenotaphrum secundatum), which grows in the area roughly covered by U.S. Department of Agriculture plant hardiness zones 8 through 10. Another common herbicide, atrazine, is potentially lethal to grass when applied in temperatures above 85 degrees Fahrenheit. Use the instructions on the bag of each weed and feed product to determine how it will affect seeding.
- University of Florida IFAS Extension: Weed Management in Home Lawns
- Texas Agricultural Extension Service: Maintaining St. Augustinegrass Lawns
Sara DeBerry is a graduate of the University of Florida holding a masters degree in environmental horticulture and a minor in entomology and nematology. DeBerry has been writing for government agencies since 2004 and has published peer reviewed scientific articles during her studies at UF.
My Most Important Fall Lawn Tip
Here’s a little known lawn secret: If you have a Bluegrass, Fescue or Ryegrass lawn, your grass roots are still growing in your soil that is warmer than air temperatures. Even if you’ve already fed this fall, another feeding now can really help build your grass roots. So put on your gloves and ear muffs and get out your lawn spreader, and feed your lawn one more time with Scotts Turf Builder WinterGuard.
You won’t be alone. Expert turf researchers will be doing the same thing with their lawns. For example, Ohio State University turf experts say you should get your last winterizing feeding down by the middle of November. Virginia Tech, Penn State and Michigan State Agronomists also agree that you get a big benefit from a November feeding. So, even if you are in the far north, this coming weekend is not too late to get your lawn fed.
I have more good news for you. Rather than raking your tree leaves, save time by mowing them to dime size just prior to feeding. This will help them “compost on your lawn”. This video from Michigan State turf agronomist Rebecca Finneran shows you how you can “throw away your rake” this fall.
One last bit of advice. If you’ve got weeds and want to spread Turf Builder WinterGuard with Plus 2 Weed Control instead of Turf Builder WinterGuard, your mid-day temps need to still reach 60 degrees the day you apply.