Fertilizer for Horse Pastures
By Eleanor Blazer
Just like horses, pastures need proper nutrition.
Fertilizer can provide the nutrients which the soil may be lacking. But, what do the numbers mean?
Commercial fertilizer products will have three numbers, for example: 23-10-22. The first number represents the nitrogen content; the second the phosphorus and the third is potassium. Each of these ingredients provides a specific nutrient needed by the plant.
Nitrogen promotes leaf growth. It stimulates growth of new seedings and assists with re-growth after grazing. Nitrogen is an important component of chlorophyll, which makes the plant green.
Phosphorus promotes root and stem growth. It strengthens the plant.
Grass varieties have fibrous root systems and are able to extract phosphorus already present in the soil. Phosphorus will not easily leach from the soil. For these reasons the phosphorus included in a fertilizer will have a low number.
Potassium increases plant vigor and helps maintain a healthy plant. It aids in the plant's ability to tolerate stress (heat, drought, cold and intense grazing). Potassium also helps the plant fight off disease.
Potassium is very soluble and will leach from the soil. The amount in a fertilizer mix developed for pasture will be high.
A soil test can help you determine the type and amount of fertilizer needed to provide the lacking nutrients.
According to the Ohio State University Extension, horses do not need to be removed when applying granular fertilizer. Avoid any spills of fertilizer where a horse could eat enough of the material to be toxic. (OSU does recommend horses be removed from the pasture if liquid fertilizer is used - wait until rain washes the fertilizer off plants.)
If you have limited a limited amount of money to spend on pasture management use that money to insure the pH is correct. Grasses need a pH level of 6.0 to 7.0. No matter how much fertilizer is applied, if the pH is incorrect the plants will not utilize the nutrients in the fertilizer. You will be wasting money on ferilizer if the pH is incorrect. Lime is used to correct a low pH. The best way to know if you need lime is to soil test.
Continuous close grazing will kill plants. Horses should be removed from the pasture when the plants have been grazed to a height of 2 to 2 ˝ inches. A minimum of 30 days rest should be allowed for the pasture to recover - this time will be longer if a drought occurs.
There's nothing prettier than watching horses graze on a beautiful pasture. Do what you can to keep the plants healthy.