Proper mowing of your lawn can kill weeds and chinch bugs, cure disease, save water and provide fertilizer. However, improper mowing can be harmful.
Mowing is stressful to grass because it is meant to grow tall, mature and make seeds. Man decided that lawns look better when freshly mowed and most people feel the shorter the better. But a close cut doesn't do much for your lawn or your water bill.
Grasses are basal-growing plants. The growing point is at the crown (the area between the root and the blade) of the plant near the soil line. The tips are the oldest part of the blade which means you can cut off their tops without killing them. When you cut the tips, new growth pushes up from the crown. When the mower cuts off those grass tips, it causes severe shock to the grass plant.
Grass lives primarily on food manufactured in its blades not on what is drawn up through the roots. Cutting the blades reduces the ability of the plant to manufacture food. That food is used for both top and root growth so the shorter you cut the grass the less root growth you will have.
A plant with deep roots will be better able to withstand drought, fight off disease and insects and store food manufactured in the leaves. So, the longer the root the healthier the grass. Every time the grass is cut the root system is weakened to some degree. When cut too severely, the roots stop growing. Mowing tears, the plant and creates ports of entry for disease. Sharp mower blades give a cleaner cut which heals faster. Another problem with close cutting is that it allows sunlight to dry the soil and the additional light will encourage weed seeds to germinate.
Mowing has tamed the wild grasses of our past. Mowing grass before it sets seeds prevents sexual reproduction and many grasses respond by reproducing asexually by spreading stolons and rhizomes creating a thicker lawn. How high you mow will also influence the spread of the grass. A higher cut makes healthier grass with deeper roots, more mass for photosynthesis and more stolons and rhizomes for a thicker sod which means less weed invasion.
You should also consider that grass grows at different rates throughout the seasons. The summer months require more frequent mowing than our cold winter and dry spring months when you should not cut as often. Our coming cold weather will slow the growth and bi-weekly mowing will be all that is needed. Some lawns could go three weeks or a month without mowing. If the grass doesn’t need to be mowed save it from the extra stress and don’t mow it. As we move into the dry spring months grasses will be stressed by heat and drought, so care must be taken to properly irrigate to help ease the stress of mowing.
In past years drought required the city to reduce our allowed watering to once a week. The fact is our lawns could easily survive on this schedule and be healthier for it. We should use horticultural practices every day which produce deep-rooted lawns that don’t require excessive water to keep them green. All lawns, properly cared for, could be conditioned to require no more than once a week watering all year. The exception would be during the cold winter months when once every two or three weeks will do. I remember the year the phase three water restriction took effect on Marco Island and everybody thought their lawn would surely die if watered only once a week.
People were surprised as their lawns remained green and lush. It was because it was during the winter months with the cooler temperatures and lower evaporation rates. That benefit ends as the temperatures begin to climb in March, April and May. Spring is when the benefit of a deep root system and tall grass blades come in to play to allow for less watering.
Check your irrigation system to be sure of proper coverage. It may seem that the sprinklers are reaching all areas but if you have dry spots on the edge of your sprinkler pattern you may not be getting adequate water at the edges of the sprinkler pattern. Place some empty tuna cans at the center of the green areas and in the dry areas and measure the water levels after the zone has run. You’ll most likely find you’re not getting enough in the dry areas. This could be dirt in the sprinkler tip, heads not properly spaced or water pressure problems when the sprinklers are running in the wee hours of the morning. When not mowing every week be sure the sprinkler heads stay well cleared of taller grass blades to allow for proper coverage.
It was once believed that grass clippings were the cause of thatch accumulation in the lawn. It is now known that they do not accumulate unless the clippings are exceptionally long. They break down soon after they hit the ground. In the process they return a lot of nitrogen to the soil. Clippings are a very good thing and should be left to break down and feed your lawn. Just be sure to keep them out of the waterways where nitrogen is not so welcome.
A lush, green lawn is a beautiful thing. It doesn't need excessive fertilizer, chemicals and water use to look that way if you just raise the mower deck as high as it will go. A deeper lawn is a healthy lawn!
Eileen and Peter Ward have owned a landscape and lawn maintenance company for 35 years. Eileen can be reached at Gswdmarco@comcast.net or 239-394-1413.