Question
QUESTION: Good Morning Long Island.  My lawn looks very good this summer, except when I mow it.  I water it a few times a week with an autosprinkler.  But after mowing the lawn looks like it was burned even though it was green when I started to cut it.  Then I water it and the lawn recovers.  I am not mowing the grass too low, the setting for the blades is on "Medium". What's going on and what should I do differently, if anything?  Appreciate your advice.  Art.

ANSWER: When's the last time you sharpened your lawnmower, my friend?

Lawnmower blades should be sharpened frequently for rotary mowers, less for reels (my German engineered reel mower gets sharpened every 4 or 5 years).  Dull blades shred Grass instead of slicing through it; the damage shows up as frayed brown edges that need to recover.

How often are you mowing your Lawn?  Once a week at this time of year may not be enough if you are growing Grass in a cool Grass state up north.  I live in a transition zone, where Kentucky Bluegrass and Fescue take off during spring and autumn but nap during the hottest summer heatwaves.  If your weather is still Bluegrass-friendly, it may just need to be mowed more often.  Otherwise you end up cutting it down more than 1/3rd of the way.  And as you know (I hope), Grass should NEVER be mowed more than a third of its height; that kind of damage, it never recovers from.

What kind of Grass do you have out there?  Give me a little more info and I'll help you solve your problem.  Thanks for writing.

---------- FOLLOW-UP ----------

QUESTION: To answer some of your questions, I have a 1 acre plot surrounding my old house in historic Providence, Rhode Island.  I have been casually over-seeding every year in autumn with a quality "Sun" mixture from a supply store in town.  I am somewhat careless about sharpening perhaps.  It is something I only tend to once a year.  The autosprinkler was an investment that enhances the value of the property for resale but I do not have plans to move anytime soon as I am allready semi-retired.  If you have any further suggestions I would appreciate knowing them.

Answer
OK - a 'quality Sun mixture from a supply store'...  That's a cool Grass seed that we can narrow it down to.  Make sure that 'Medium' setting translates to a 2 1/2 inch mowing height for your Grass -- nothing shorter.  Keep it sharpened and find someplace convenient that will do it at least monthly.  You should mow your Lawn AS MUCH AS POSSIBLE to minimize Weeds and maximize Grass health.  You cannot mow too much.  It's GOOD for your Grass.

Turn off the 'autosprinkler'.  You do not need to use it except to keep it in good working order so that when you sell your house it will be a nice little luxury feature.  I am surprised they install those in Rhode Island.  Do you really need them?  Does it EVER hit 90 degrees there?  Does it EVER get dry?

The only other suggestion I have is to fertilize once a year with a good, slow release Nitrogen fertilizer like Milorganite.  A top dressing of Alfalfa Meal, Bloodmeal or other organic high-Nitrogen fertilizer would be even better, but could be prohibitavely expensive on a full acre of Lawn.  Fish Emulsion and Manure are cheaper but too smelly.

Let me know if you have any more questions.  Thanks for writing.