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The Best Fertilizers for Grass

When trying to decide what fertilizer to use for your lawn grass, all the different styles and varieties on the market can be confusing. Most fertilizers consist of three major elements: nitrogen, phosphorus and potassium (which is represented in the three numbers on the label). If you don't know the health of your grass, do a pH test in order to figure out the best fertilizer for you.

Potassium Fertilizer

Potassium helps toughen up weak grass roots and blades. If your lawn has thin grass blades that are easily killed or pulled out, use a potassium rich fertilizer. This type of fertilizer will also help your lawn learn to tolerate drought, disease, cold weather--and toughen it up in general.

Nitrogen Fertilizer

Nitrogen is one of the most important elements to grass health. It helps encourage grass to evolve into a rich green color, as well as make it grow thick and dense so you have a full, healthy lawn. Once your grass is sturdy and thick, this will help ward off disease and insects much more easily. Look for a fertilizer high in nitrogen to make your lawn as healthy as possible, as well as dense.


Phosphorus fertilizers are best for grass that needs very strong roots. This could be because of poor soil conditions, and weather, such as if you live in an arid, dry area where the roots need to dig deep for water. Once grass roots have established deeply, they will grow dense, crowding out any weeds or chances of disease.

Fertilizers Recommended For Centipede Grass

Like other grasses, the nutrient that centipede grass requires most is nitrogen. The maximum amount of nitrogen that a centipede grass lawn should receive in one year is 2 pounds per 1,000 square feet. You can apply up to 1 pound in the spring and 1 pound in later summer or early fall. If centipede grass develops a yellowish appearance or if soil tests reveal an iron deficiency, the lawn will also benefit from an iron spray. Repeated problems with an iron deficiency may indicate an overly high soil pH. For soils with low potassium levels, such as sandy soils, some extra potassium fertilizer will help centipede grass stay healthy throughout winter. You can test soil pH yourself with at-home testing strips. Dolomitic limestone will also add some calcium and magnesium to the soil.

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