Question
Hi Floyd...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
Good Evening Bob:
First I believe you need to change your watering schedule. Watering should be done deeply and infrequently to promote deeper rooting. It is not the number of times you water your lawn that is important, it is the amount of water necessary to achieve a saturation depth of about three inches. That is usually about one inch of water per week. It is possible that your lawn is not being saturated enough at any one watering.
The best way to know when to water is determined by observing the appearance of your lawn.  Turf that needs water will not spring back up after walking on it. Bluish-purple wilting blades and folded or rolled blades are good signs that the lawn should be thoroughly watered.
Keep in mind that watering heavily and then abruptly stopping  makes the grass much less able to endure warm, dry periods. Once you begin watering it must be continued throughout the heat of the summer months.
A good way to check the amount of water applied is to set out a series of straight sided containers under your sprinkler system (Tuna cans, Cake pans etc.). Time how long it takes until the one inch level is achieved. You can then use this time figure for future watering without using the cans.
Your soil type will determine the watering application.
Loamy or silty soil need receive only one application of water per week.
Sandy soils should be watered twice a week with ?inch of water at each application.
Clay soils may need to be watered slowly with several applications during the week to allow the water to soak in properly.
Watch for runoff during the watering period. It is possible that your lawn will not be able to soak up the water as fast as your sprinkler is putting it down. If this occurs shut off the sprinkler for an hour and then turn it on again.
The most efficient time of day to water is late evening and early morning (between 9 p.m. and midnight and/or 7 and 9 a.m.). It is usually less windy, and cooler at this time, resulting in less evaporation and more efficient use of water. Water pressure is usually better and this results in better water distribution. University research has shown that watering at night does not encourage disease development.
Keep in mind that healthy turf brought on by proper mowing, fertilizing and cultivation, uses water more efficiently.

Second I believe your mower blade needs to be sharpened. It appears that it is not cutting the grass blades but beating and fraying them instead. During the season, regularly check your mower blade for sharpness and balance.
Sharpen rotary mower blades every fourth mowing, especially when mowing fescue or ryegrass lawns. A dull mower blade will shred and fray leaf blades instead of cutting them cleanly. The result is a brown, unattractive lawn.
The two most important facets of mowing are mowing height and frequency. The minimum height for any lawn is 2 inches. The preferred mowing height for all cool season grasses is 2 1/2 to 3 inches. Mowing to less than 2 inches can result in decreased drought and heat tolerance and higher incidence of Insects, diseases and weeds. Mow the lawn at the same height all year.
Mow the turf often enough so no more than 1/3 of the grass height is removed at any single mowing. If your mowing height is 2 inches, mow the grass when it is 3 inches tall. You may have to mow a bluegrass or fescue lawn every three to four days during the spring when it is actively growing but only once every seven to 10 days when growth is slowed by heat, drought or cold.
If weather or another factor prevents mowing at the proper time, raise the height of the mower temporarily to avoid cutting too much at one time. Cut the grass again a few days later at the normal mowing height.
Let grass clippings fall back onto the lawn, unless they are used for composting or mulching elsewhere in the landscape. Grass clippings decompose quickly and provide a source of recycled nutrients and organic matter for the lawn. Mulching mowers can do this easily. Side-discharge rotary mowers also distribute clippings effectively if the lawn is mowed at the proper frequency. Grass clippings do not contribute to thatch accumulation. If herbicides are applied to the lawn, do not use clippings in the vegetable or flower gardens. Keep them on the lawn.

Have a good lawn!
Floyd McMahon