Ron Ernst's garden, Thomasville, Georgia. Photo: Steve Bender

I look at lawns as I silently walk through my neighborhood each morning, exercising my hyper-critical eye. Some lawns lush and green. Others are 30 shades of brown. What is the one mistake that turns a soft, cool carpet into a weedy, scraggly plate of pebbles? It isn't what you might think.

No, it has nothing to do with water. Rather, it's the result of doing one of the fundamental tasks of lawn care all wrong. Mowing too low.

Mowing the grass near or just above the soil surface is called "scalping the lawn." Roll that phrase around in your mind for a moment. Does that sound like something that's beneficial? If it does, I will be happy to store leaky drums of radioactive waste from the Fukushima-Daiichi nuclear reactor on your lawn for a nominal fee of $100,000.

Why do people scalp their lawns? For the same reason they butcher their crepe myrtles and carve their bushes into ugly meatballs and squares. Because they see their neighbors doing it and assume they know something we don't. Only the neighbors know nothing. Such copycat behavior is how our society wound up with leisure suits, Ford Tauruses, white Zinfandel, and every show on TV now being centered on vampire sex.

I, of course, never watch such programs.

How Scalping Ruins Your Lawn Grass (I'm talking the legal kind here) is a plant. Grass blades are its leaves with which it turns sunlight into food. Lots of food encourages the growth of a vigorous root system. Healthy roots produce more grass blades and you get a thicker, lusher lawn.

When you scalp the lawn, you temporarily halt all food-making. Without food, roots stop growing and grass plants weaken. They spend their remaining reserves on growing new blades. Scalp them again and you're well on the way to killing your lawn. The only plants that will thrive are weeds that don't mind scalping, such as dandelions, crabgrass, and cudweed. Soon your lawn looks like this.

emIf you keep scalping it, watering ain't gonna help. Trust me. Photo:

How to Avoid This Terrible Fate It's simple. Raise the mowing height of your mower. And mow often enough so that you never remove more than 1/3 of the grass blades in a single mowing. That means if your grass is three inches high, don't mow it lower than two inches. If you need to mow it shorter than that, do so in two mowings spaced 3-4 days apart.

But why mow low at all? Mow your lawn HIGH -- well, not "high" as in under-the-influence, but high as in "tall." Tall lawns need far less maintenance than scalped ones. They need a lot less water, less fertilizer (especially if you use a mulching mower), and less frequent mowing. And during droughts, they'll stay green long after your neighbor's short lawn has turned the color of vanilla wafers. For example, my Bermuda grass lawn is still green today after three weeks of NO water.

What's the lowest you should cut your lawn during the summer? Two inches. Doesn't matter what kind of grass you have. Two-and-a-half inches is even better for most kinds. Three inches for tall fescue and St. Augustine.

Stop scalping your lawn! Don't copy the neighbors. Grumpy has spoken. So it shall be done.