Lawn Mowing Height
Question: How often should I mow my lawn? My neighbor lets his lawn grow up to about 3 inches and then whacks it back to less than an inch. Isn’t it better to mow more frequently?
Answer: Yes, you will have a much better lawn if you mow at least once per week. It is very hard on the lawn when you let it grow tall before cutting. It becomes thinner, weaker, and is much more likely to be invaded by weeds.
The frequency of mowing is directly related to the mowing height. A maximum of 40% of the leaf blade should be removed at each mowing. So if you mow at 2 inches, it should be mowed when it gets to about 3 ½ inches. If you mow at 1 inch, it should be cut by the time it reaches about 1 ¾ in inches. Most lawns will grow more than ¾ inch in a week. Golf course fairways are usually mowed at 2 to 3 day intervals so they can be mowed at less than an inch.
The root system of a lawn is in direct proportion to the top growth. A lawn mowed at 2 inches will have twice as many roots as a lawn mowed at 1 inch. That extra root system can be very important during hot summer weather. The interval between irrigations can be increased with a larger, deeper root system. That will save some money on your water bill.
Another practice that will improve lawn quality if you mow frequently is to allow the clippings to remain on the lawn. These clippings will fall between the leaf blades if you use a mulching mower which chops them up into fine pieces. The clippings are used for food by earth worms and soil micro-organisms. They are converted to fertilizer nutrients and the equivalent of one fertilizer application is added to the soil in a year’s time.
Leaf density will be thicker with frequent mowing. This leaves less space for weed invasion.
Allen Wilson
Allen has been writing about gardening for over 30 years. He is a retired professor of Horticulture.