Question
Hi Mark..I live in RI and lately it's been hot and humid. My lawn has been looking pretty good, I use my sprinkler system to water it several times a week. But, after I cut my lawn, it looks burned, even though it was green before I cut it. Am I doing something wrong? Usually when I'm done cutting it, I'll put on the sprinklers and the greens up again. I've leave my mower on a medium setting, so I don't cut the grass too low. Do you think it's a watering problem or should I cut the lawn more often to avoid it looking burned out right after cutting? Thanks for your help!

Answer
Bob,

I know what you mean.  I've got places that do the same thing, or something similar. I think its got to do with grass variety, and maybe one time you let it grow more than your usual one week.

There are certain varieties of grass that tend to get woody or "stemmy" if I let them go a little too long.  So rather than just long blades, I get stringy  or sometimes stiff stems with long blades on them.  When I cut the blades of grass low or off, I'm left with the stems and lower leaves which look brown, straw-like, burned out.  

So yes, I think you're on the right track about mowing frequency to prevent this.  If during peak grass growing season (here it's APR & MAY) you mow more often.  A rule o'thumb is to try to not remove more than a third of the blade per mowing.  More than that stresses the plants out and doesn't produce thicker growth.

As relief,  you can overseed the areas you are concerned about with a type of grass that doesn't do that so much.  Here I stick with perennial ryegrass.  Overseed at a rate of 5lbs/1000 sq ft.

One other thing.  Grasses don't all thrive at the same heights.  I've got a chart around here, which I can't find right now, that gives some recommended mowing heights. I'll pass it on if I find it.  I know perennial ryegrass is best at 2-2.5 inches (thickest, greenest, most drought resistant).  That's really long for some folks.  So maybe there's a problem with the type of grass you've got, and the height you prefer.

For what it's worth,
Mark in Portland