A Green Lawn

Seven years ago; I owned a large landscape company with $885,000 in commercial lawn care contracts which amounted to forty plus acres of turf to maintain. Needless to say; I could not afford to drop the ball and not have those commercial grounds as green as possible -
How do professional contractors keep lawns green?
Step One: Never get behind, or in other words, never let the turf get stressed in the first place. Playing catch-up on a lawn in July, that did not have adequate water in June, is going to be a loosing situation. If the weather forecast calls for an increase in heat next week - bump the water up now.
Step Two: The same goes for fertilizer, do not wait until the lawn starts to loose it's color to add nitrogen - you're back to playing catch up. That is why I really endorse the time release fertilizers that activate with heat (see Spread it & Forget it).

Step Three: Mow the lawn at 2 1/2 inches in the Spring with the intent to raise the mowing deck as soon as you know it is going to get hot. Each heat increase; raise the deck a half inch. In the extreme heat of late July and August you should be as high as your deck will go; which on most home owners mowers is 3 1/2 inches. The taller grass shades the ground slowing evaporation and the longer stem is supporting the root structure during this stress time.

This is how you keep your lawn green!