Well, they say the best time to start a new lawn is in the fall or spring. That may depend on your location I guess, but that's for where I am (new york). You'll have to keep them well watered no matter what. Sprinkler on a couple of hours at least once, prob twice a week. Maybe thats why people put the bottles of water out. (I'm assuming to slowly drip and keep ground moist) Hope I could help.