Can you please give me a few suggestions for killing wild onion in my lawn? I have sprayed with 2,4-D and also Round-Up, but the onions just keep multiplying?
Wild onion, as you found, is a difficult weed to control. It spreads by forming underground bulbets and by seed. Proper mowing, watering, and fertilization will keep you lawn healthy and better able to crowd out these and other weeds. Regular mowing prevents flowering and seed set so additional seedlings won’t develop. Unlike other weeds the best time to spray wild onion is right after mowing the lawn. The cut stems better absorb the weed killer. Repeat as needed when the plants are growing and recently mowed. Broadleaf weed killers with 2-4D or total vegetation killers like Roundup (protect the nearby turf) will eventually kill the wild onion in your lawn. Avoid treating centipede and St Augustine grasses during spring green up.