Left unmowed, lawn grasses go to seed, but the self-seeding process is not necessarily the best way to bulk up a lawn. The value of self-seeding depends on the species or variety of turf grass as well as competition from weed species that germinate and grow at the same time.

Will grass seed itself?

Regularly mowed lawns typically do not seed themselves because grass cannot produce seed unless it develops flowers. However, many species of grass are capable of spreading out vegetatively from side shoots that grow above or below the soil.

Is it bad to let your lawn go to seed?

Tip. Check with your homeowner's association, if applicable, or your municipality before you let your lawn grow high enough to develop seed. Some grasses don't seed until they are about 12 inches high, which may not be allowed by your HOA or your city. Not all grasses produce viable seed.