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The best time to plant grass seed depends on your local climate and whether you have cool-season or warm-season grass.

For cool-season grasses (like tall fescue), the ideal time to seed is late summer or early fall (typically August and September). During this period, the soil is still warm from the summer, but the air is cooler, creating optimal conditions for germination and root establishment before winter. There is also less competition from weeds. Spring is a secondary option, but cooler soil temperatures, the risk of a late frost, and less time for the grass to mature before summer heat can make it less successful.

For warm-season grasses (like St. Augustine), the best time to plant is from late spring through mid-summer (typically May and June), when temperatures are consistently between 75 and 90 degrees Fahrenheit.

In general, it is best to avoid seeding during winter or early spring, as cold soil and air can prevent seeds from germinating. For recommendations tailored to your specific grass type and climate, consider consulting a local lawn care professional.

Soaking grass seeds in water before seeding is called pre-germinating. It’s not necessary but can be very helpful in some cases. Some grasses like are very slow to germinate, and basic seeding on the ground is unlikely to be effective—that’s especially true of cool season grasses like Kentucky bluegrass, rye grasses, and Bermuda grass. Soaking these seeds in a bag or bin of water for one to four days beforehand can give the grass the start it needs to survive.

While it’s possible to grow grass seeds by throwing them down, this isn’t the best way to plant them. By amending and prepping the soil beforehand, you’re providing optimal contact between seed and soil for a better chance at germination. If you throw them down without preparing the soil beforehand, seeds are more likely to blow away, get eaten by hungry birds, or never grow.

Always mow the lawn on a short setting when overseeding. The thinner coverage offers more space for the grass seed to take root in the soil. When reseeding a lawn, however, you may need to remove your old turf altogether.