Weeds among new grass are common: bare soil and frequent watering can help weed seeds sprout alongside lawn seed or new turf. The safest approach is usually to keep the grass growing well and remove weeds selectively by hand, rather than reaching for a weedkiller. Before starting, identify whether your lawn is newly seeded or laid as sod, and check the grass type and any product labels. New grass is easily damaged, and treatment timing depends on how it was established.
What You’ll Need
- Gardening gloves and a hand weeder or narrow trowel
- A watering can or hose with a gentle spray setting
- A clean bucket or garden waste bag for pulled weeds
- Optional: a lawnmower, once the grass is ready to be mowed
Step-by-Step
- Work out what is growing. Look closely at the leaves and growth habit. Some seedlings that look like weeds are simply young grass, and some plants, such as clover, may be acceptable in a lawn. If you cannot identify a plant, take a clear photo or ask a local garden center or extension service before removing or treating it. Avoid disturbing new grass while investigating.
- Check how recently the lawn was planted. Grass seed needs time to germinate and establish roots; sod needs time to root into the soil beneath it. Follow the seed or sod supplier’s care instructions, especially for watering and mowing. If you have just seeded, do not rake, dig, or walk across the area to chase small weeds. For recently laid sod, avoid pulling weeds if doing so would lift or tear the turf.
- Keep the grass growing, not the weeds. Water according to the establishment instructions: seeded soil is generally kept consistently moist at the surface while seeds germinate, without puddling or washing seed away. As seedlings grow, gradually water less often and more deeply, as appropriate for your soil and weather. Once sod has rooted, adjust to deeper, less frequent watering. Excess water can encourage weeds and disease, but letting new grass dry out can kill it.
- Pull a few established weeds carefully by hand. When the soil is slightly moist, grip the weed near its base and ease it out with as much root as possible. Use a narrow weeder for a taproot, such as a dandelion, but keep the tool shallow and work away from grass roots. Fill any small hole with compatible topsoil or lawn soil and gently firm it. If the grass is too young to withstand disturbance, leave the weed for now and remove it later.
- Remove seed heads before they spread. If a weed has flowered or is about to shed seed, carefully snip off and bag its seed head where practical. Do not shake mature seed heads over the lawn or put seed-bearing weeds in home compost unless your composting system gets hot enough to destroy seeds. This reduces new weed growth without disturbing a larger patch of seedlings.
- Mow only when the lawn is ready. Wait until new grass reaches the mowing height recommended for its species and is firmly rooted. For seeded lawns, a common readiness check is that seedlings are several inches tall and do not pull up easily, but follow your seed supplier’s guidance. Sod should resist a gentle tug before mowing. Use a sharp blade, remove no more than about one-third of the grass height, and avoid turning sharply on tender turf.
- Delay herbicides until the grass is established. Do not apply a general weedkiller or a broadleaf lawn product to newly seeded grass or fresh sod unless its label specifically permits that use at your lawn’s age and grass type. Many products require several mowings or a stated waiting period after establishment. Read and follow the label exactly, including application rate, weather limits, protective equipment, and restrictions for children, pets, and nearby plants. Never assume a product safe for mature lawns is safe for new grass.
- Reassess after the grass thickens. Keep monitoring the area and remove easy-to-pull weeds as the lawn strengthens. A dense, well-established lawn competes better with weeds. If a patch remains bare after the recommended establishment period, identify the cause, correct watering or soil problems, and reseed according to the product instructions rather than repeatedly applying weed treatments.
Common Mistakes
- Using weedkiller too soon: Herbicides can injure or kill young grass. Follow the label’s minimum establishment period; if it is unclear, do not apply the product.
- Pulling weeds aggressively: Digging deeply can uproot seedlings, loosen sod, or leave large bare holes. Remove only weeds you can lift without damaging the lawn.
- Watering constantly after germination: Keeping the surface wet indefinitely can favor weeds and shallow grass roots. Adjust watering gradually as seedlings establish, while preventing them from drying out.
- Mowing too early or too short: Young roots may be pulled out by a mower, and scalping stresses the lawn. Wait until it is rooted and mow at the appropriate height for the grass species.
- Overseeding without fixing the cause: New seed may fail again if the soil is compacted, drainage is poor, or watering is inadequate. Diagnose the bare patch first.
Tips
- Use the seed or sod packaging to confirm the grass species and recommended mowing height; lawn care varies by species and climate.
- Work from boards or stepping stones at the edge of the lawn if you must reach a spot, and avoid repeated foot traffic on wet or newly rooted areas.
- Take photos of unfamiliar weeds and note where they appear. A small number of annual weeds can disappear with regular mowing once the lawn is established; persistent perennial weeds may need targeted control later.
- Keep mower blades sharp and clean. Do not mow when the soil is saturated or the new turf lifts underfoot.
Troubleshooting
Weeds are appearing faster than grass: Check that seed has not been buried too deeply, washed away, or allowed to dry out. Follow the seed supplier’s germination instructions and avoid treating the whole area with herbicide. If the grass is patchy, wait until the recommended reseeding window for your region and seed type, then repair bare areas.
Grass comes up when I pull a weed: Stop pulling in that area. The roots are not established enough. Snip off visible weed tops or leave them temporarily, keep the grass cared for, and try again once the turf resists a gentle tug. Do not fill disturbed patches with loose soil that smothers surrounding seedlings.
The new grass is yellowing or thinning: Weeds may not be the cause. Check for waterlogging, drought, poor seed-to-soil contact, disease, or damage from foot traffic. Correct one likely issue at a time, and ask a local lawn professional or extension service if symptoms spread or you suspect a pesticide injury.
A weedkiller has already been applied: Check the product label immediately for watering or other follow-up directions, and do not apply more chemicals. Note the product and application date, keep people and pets away for the label’s specified period, and contact the manufacturer or a local expert if the grass is damaged. Do not try to neutralize a product with another chemical.
Frequently Asked Questions
Should I pull weeds from newly seeded grass?
Only if they come out easily without disturbing seedlings. Otherwise, leave them temporarily, remove seed heads if possible, and wait until the grass is better rooted.
Can I use a weed and feed product on new grass?
Usually not during establishment. These products may contain herbicide or fertilizer that can harm young grass. Use only if the label specifically allows it for your grass type and stage, and follow its directions.
Will weeds kill new grass?
A few weeds rarely ruin a lawn, but dense weeds can compete for light, water, and nutrients. Prioritize keeping the grass healthy and deal with troublesome weeds carefully.
When can I spray weeds in a new lawn?
There is no universal waiting period. It depends on the product, grass species, and whether you seeded or laid sod. Follow the label’s establishment and mowing requirements; if it does not clearly permit use, wait.
Is clover a weed in new grass?
That depends on your preference. Clover can be part of a mixed lawn, so you do not have to remove it. If you want a grass-only lawn, wait until the grass is established before choosing a labeled treatment.
Can I mow weeds before the grass is ready?
No. Wait for the grass to reach its recommended mowing height and be firmly rooted. Early mowing can pull seedlings out even if weeds look tall enough to cut.