Before the hottest part of the day. Lightly rake the soil loosening it up so that the new seeds can make good contact with the soil surface. How To Seed A Lawn Planting Grass Seeding Lawn Lawn Care Ideally the best time of the day to water your grass is during the early morning. Best time to water grass seed . A water timer can simplify the process of when to water grass seeds so you can easily and efficiently water your newly seeded lawn with no hassle at all. Grass seed germinates and grows best in dirt that is loose and not compacted. Are the best as there is considerably less wind to blow the water away from the soil. Watering 1- 2 times per week is more beneficial than light watering several times a week. Water 1-2 times a week applying a total of approximately 1 inch of water each week based on your location and time of year. The Best Time to Plant Cool-Season Grass Seed. For example Minnesotans in the Upper Midwest seed cool-season lawns from mid-August to ...