How long to wait after hyroseeding?

[mr lawn]

I have a commercial account that I have had for a year now. They are going to tear down the exisiting store and replace with a new bigger one. In the process they are going to get more lawn. My question, they are hydroseeding the new lawn. Probably the 2nd week of may, how long do I need to wait to make the first cut, ( any specific height ) . They will have a sprinkler system, so I know they will be watering. Any help would be great.
Thanks
Mr Lawn

[strickdad]

you need to tell us what type of grass they seeded with ..

[Runner]

When it starts getting to a regular mowing height. Just don't take too much off, especially on the first cuts. If your cutting at 3", than cut it when it's about 4" tall. Just like regular mowimg, even if it's thin. What you DON'T want to do, is wait until it gets real tall, thinking that your doing it a favor by letting it "fill out" or something.

[Shawn Burns]

When i hydroseed a lawn, i tell customer to cut it as soon as there is enough grass to cut. If it is cool season grass, when most of it gets about 3 inches tall cut it at 3 inches. If it is warm season grass, when it gets 2 1/2 inches, cut it at 2 1/2 inches. One thing that helps is to turn off water 2-3 days prior to mowing to let the ground firm up a little so as not to leave ruts.