Do I weed and feed or seed first?
David Ramirez
Published Jun 04, 2026
Do I weed and feed or seed first?
Many of our clients often ask us the question, “Should I plant grass seed or kill the weeds first?” The answer is rather simple. The weeds should be killed first. Any weeds and poor looking grass around the lawn should be killed before any seeds are planted.
Does weed and feed kill grass seeds?
Even with careful preparation of the planting site, weeds can still develop among the newly planted grass seed. Weed killers, however, can harm grass seeds and seedlings if applied too early or improperly.
How soon can you plant grass seed after using weed killer?
All weed control products are different, but in general, it is not recommended to plant new grass within 4 months of using a crabgrass preventer, or within 1 month of using other weed control products. (Unless the product is designed to be used when seeding.)
Will Preemergent kill grass seed?
Pre-emergent herbicides don’t actually kill weed seeds before germination. Instead, they fatally interrupt their growth process in some way to prevent the seed from getting all the way through the seed germination stage. For that to work, it has to be in the soil at the right time — at the right temperature.
What is the best grass seed and weed killer?
BEST OVERALL: Scotts Turf Builder Weed and Feed.
Should I kill crabgrass before seeding?
You can overseed into existing grassy weeds like crabgrass and then apply pre-emergent crabgrass killer the following spring to remove crabgrass from your lawn. Do not plant new seed if you applied pre-emergent crabgrass killer earlier that growing season. The crabgrass killer will also kill germinating turfgrass seed.
How does weed and feed work on grass?
Weed and feed products work by preventing new growth, effectively stopping weed seeds from sprouting and newly sprouted weeds from flourishing. The herbicides used aren’t specific enough to only target weeds, however; they’ll do the same to grass seeds and any new grass growth.
Do you weed and feed or plant seed first?
Do I Weed & Feed or Plant Seed First? You can sow grass seeds now and kill weeds later with a post-emergent herbicide or kill weeds now with a pre-emergent herbicide and plant the seeds later.
Can You reseed your lawn with weed and feed?
Weed and feed products aren’t ideal for all situations, though, and may cause some problems if you plan to reseed the lawn soon after their application. As the name implies, weed and feed products contain both a fertilizer and an herbicide to control weeds while feeding the surrounding grass.
Is it OK to use Weed and feed in spring?
Weed and feed products designed for early-spring application usually contain pre-emergent herbicides. They work by preventing weed seeds from sprouting, and they can be an effective way to control crabgrass and some broadleaf weeds. Trouble is, this assumes that you’ve got weed seeds in your soil ready to sprout.
