There is not necessarily a best time to hydroseed, but different times throughout the year can work. Fall and spring are great times for those looking to save money and water. Hydroseeding in the summer also works if homeowners want the grass to grow as quickly as possible, since hotter weather speeds up the germination process. However, the lawn will need to be watered more often this time of year. It’s generally advisable to avoid hydroseeding in the winter, as grass is usually dormant in the cold weather.