Question
i have a irrigation system and my lawn is healthy and green even with these high temps. is there a fertilizer i can use or should i wait until the fall to hit it again ?

Answer
The way I see things, Greg, Cool Season Grass responds best to a mid-Summer rest.  Hot days like we've seen this year make it miserable.  Warm Season Grass is another story -- there's nothing like a HOT Summer Day followed by a HOT Summer Night to bring out the best in St Augustine Grass or Bermudagrass.

But there are lots of folks who love to push their Grass to the limit and keep it fluorescent Green all through the hottest days of the year.  If nothing else, it keeps the Weeds from getting out of hand.  Mowing like a maniac will maintain even, vigorous growth by stimulating tissue, the way pinching stimulates bud growth on lateral shoots.

If you decide to fertilize, get a low, slow release fertilizer with small numbers.  For one thing, most of the Nitrogen in these high-dose bags evaporates soon after you put it down -- very little of it is applied under the most controlled conditions.  For another, you'll burn the microorganisms that decompose thatch and keep your Grass happy and healthy.  Get something mild and gentle.  Something that you can spell and pronounce.  Something with no Skulls and no Bones on the package, no 'WARNING' signs, no emergency medical treatments in case you drink the stuff.  That is actually the BEST thing you can do for your Grass.  I'm convinced.  Switch my vote to YES.