Consider these factors when planning out when to sow your grass seeds.
Climate
Weather conditions have a major impact on the successful germination of grass seed. Excessive rain can flood and wash away your grass seeds, while dry spells can make it extremely difficult to keep the soil moist. That’s why we recommend planting new grass seeds on a mild-weather day with projected rain a few days away.
Outdoor Temperature
It’s important to consider outdoor temperatures when planting grass seed. High temperatures can dry out soil and stress out your seeds, while cooler temperatures can impede germination. Note that soil takes longer to warm up than the air, so it’s best to wait until outdoor temperatures have lingered long enough for soil to reach the ideal temperature for grass seed.
Soil Conditions
Soil pH and nutrient content is another important factor for the best time to plant grass seed. You can use an at-home soil test or hire a local soil testing service for the most accurate and comprehensive results. Grass grows best in loamy soil with a neutral pH between 6.0 and 7.0. Amending your soil with the proper fertilizer and mix-ins will help set your lawn up to grow thick and lush. If you’re attempting to plant grass on hard soil or other difficult terrain, consider hiring a local lawn seeding service to tackle this tricky task effectively.
Also, make sure you haven’t used chemical weed killers or other herbicides recently. You should wait at least 30 days to plant seeds following herbicide treatment, but check your specific herbicide to see if it requires a longer wait period between the last application and planting.
The Worst Time to Plant Grass Seed
While the exact timelines vary by region, the worst times to plant grass seed are during the peak summer months (late June through early August) and the winter months (December through February). The excessive heat during the hottest summer months causes quick evaporation, making it difficult for soil to retain moisture. Cold temperature and frost can inhibit seed germination and slow down the growth of newly planted grass. Even if seeds germinate, they will likely struggle to survive and establish strong root systems in time for winter dormancy or spring.
Another time to avoid planting grass seed is whenever you can’t commit to watering it at least twice per day. Keeping the soil moist during germination and early growth is crucial for the health of your future lawn, so be sure you can water it yourself or hire lawn care services to ensure your seeds stay moist.