Importance of Mowing Height Mowing is the single most important lawn care task. It is often overlooked, because we do it so routinely, but mowing has a major impact on the condition of your lawn. Lawn mowing keeps your grass neat and trimmed, and how you mow will play a large roll in determining the health of your lawn. Keeping lawn mower blades sharp and setting the mow deck at the correct height are two of the most important steps to take when mowing.

The One-Third Rule and Mowing

The general rule for when and how much to mow is to remove no more than one-third of the grass in a single cutting.  For example, to keep you grass at 1 inch high, it should be mowed when it is 1½ inches high. The reason for this is is that cutting more than a third of the grass blade at one time can stunt root growth. When too much of the grass is cut off at once, the grass uses energy that would otherwise go into producing deep root systems to regrow the grass blades.

Types of Warm-season Grass

Different types of grasses have different mowing requirements. In general, grasses with thin blades and a low, creeping growth habit can be mowed shorter than wide-blade grasses that tend to grow upright in bunches.
  • Zoysia grass grows well in sun or shade and resists drought. Its slow growth habit requires infrequent mowing, but it will still form a lush lawn that tolerates foot traffic. The recommended mow height for zoysia is ¾ – 2 inches.
  • Bermuda grass likes full sun and grows quickly, needing frequent mowing. Many varieties are drought tolerant, and depending on the variety you can mow Bermuda grass between ½ and 1½ inches high.
  • Buffalo grass has good resistance to traffic from lawn equipment and foot travel. It is also drought resistant and grow in alkaline soil, but can turn brown in midsummer. It is recommended that buffalo grass be mowed between 1 – 2 inches.
  • Bahia grass needs mowed taller than other grasses, between 3 and 4 inches. It grows thickly and is a good choice for places with poor soil and full sun.
  • Centipede grass is low maintenance and can tolerate some shade. This grass has good drought resistance and does not require much fertilizer. It can be mowed at 1½ – 2 inches.

Reasons to Mow Higher

The mowing heights listed above are general guidelines. It is a good idea to mow on the higher side of the height range, or even a little higher. Longer grass shades the soil to prevent water loss from evaporation, chokes out weeds, needs mowed slightly less frequently, and survives drought better. Just make sure the grass does not become overgrown. Grass that is too tall can flop over and smother the grass beneath it, and will dull mower blades when you mow the lawn. Mowing your lawn at the correct height will help keep your grass healthy and reduce the wear and tear on lawn equipment because the mower will not be cutting through overgrown grass. Grass that is too short will stunt root growth and grass that is too tall can smother itself. But if you cut your grass at the right height without removing more than a third of the grass blade in one setting, you will be on the right track for maintaining a healthy lawn.