Cut It Tall and Let It Fall
For years I have recommended cutting fescue and bluegrass lawns to a height no less than three inches, even better four inches, for a stronger, weed-free lawn. Many people object to this height and cannot understand why I insist. The answer is simple.
Consider each blade of grass a factory. The bigger the factory, the greater the production. A tall blade of grass is capable of producing more food to feed the roots through photosynthesis than a short blade of grass. Tall blades feed a bigger and deeper root system capable of absorbing more water and nutrients from the soil and of storing more energy, which helps each blade of grass recover after being mowed.
Sow in Double Rows
You can save space and increase yields by sowing some crops in double rows. Instead of making only a single row of carrots, beets, onions, radishes and parsnips, consider making two rows six to eight inches apart. By doing so, you will be significantly increasing the volume of those vegetables in your harvest.
If the cutting blades of the mower are sharp and the mower wheels are properly adjusted, a lawn mowed to four inches tall is just as attractive as one that is mowed to two.
The taller lawn will have fewer weeds because the grass is so vigorous that it out-competes the weeds, especially those that tend to spread horizontally like crabgrass, dandelions, plantain and clover.
Tall grass tends to hide the fallen grass clippings quickly. And when you let cut grass settle down between the blades, temperatures at the base of the grass plants are cooler, and the humidity is higher, both encouraging the clippings to compost in place.
Since grass clippings contain three to four percent nitrogen, upon composting in place that nitrogen — as well as all other nutrients — is released into the soil for the roots to absorb. Thus, by cutting your grass tall and letting it fall, you recover a third to a half of the nitrogen needs of your turf.
Furthermore, if you cut tall and let the grass clippings fall, your lawn will not accumulate thatch because the clippings rot in place. Grass cut less than three inches tall loses that advantage.
When you mow, your lawn less than three inches tall, the clippings do not rot in place because, lacking shade, they tend to dry out, resulting in the accumulation of thatch, which has to be removed periodically. A lawn that is mowed less than three inches tall also encourages weeds to spread. Since the blades of grass are shorter, they form a weaker root system and are less capable of competing for light, water and nutrients.
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