Agriculture & Natural Resources
Fall nitrogen application benefits horse pastures year-round Source: Dr. Ray Smith & Krista Lea; UK Forage Extension
Fall is prime time to invest in pastures to protect them before and throughout the winter to ensure good grazing in the spring. Most cool-season horse pastures should be fertilized with nitrogen in the fall to boost root reserves and extend the grazing season. Other fertilizers can also be added in the fall, based on soil test results.
Nitrogen applied in the spring or summer significantly boosts grass growth, but many farms are unable to utilize this additional growth and ultimately mow it down instead. Rather than wasting good grass, consider applying nitrogen to cool-season pastures in the fall. Fall nitrogen will not greatly increase grass growth, but it will boost grasses’ root reserves, allowing plants to remain greener longer into winter, survive winter better and green up sooner in the spring. This effectively prolongs the grazing season. Additionally, a strong spring pasture will have better cover, which reduces annual weeds.
For best results, apply 40 to 50 pounds of actual nitrogen per acre to pastures once or twice throughout the fall. If using urea (46-0-0), increase applications to 85 to 105 pounds per acre. Applications can be anytime between September and the first hard freeze (overnight temp of less than 20°F) and should be a minimum of six weeks apart.
Nitrogen fertilizers are easily spread by a cone seeder on the back of an all-terrain vehicle or tractor. Horses do not need to be removed from pastures if equipment is operating properly and not leaving large pellet piles. Do not fertilize when grass leaves are wet, as fertilizer pellets can stick to the leaf surface and cause damage.
Unlike nitrogen, other soil amendments such as phosphorous, potassium and lime should be applied only after a soil test. Apply only the recommended amounts, as additional inputs are costly, do not benefit the pasture and have the potential to run off into nearby water bodies. While mixed fertilizer bags, such as 10-10-10 or 19-19-19 are convenient, they might not provide full fertilization of one component without overfertilizing of another.
While maintaining good soil fertility is essential to productive pastures, so is good management. No amount of fertilizer can compensate for overgrazed pastures. Fall is also a great time to assess how well pastures performed throughout the year and make plans for next year.
Rotating horses between two or more pastures provides grasses with rest and will ultimately result in greater production and fewer weeds.
For more information on soil sampling, contact the Woodford County Extension Service at 873-4601.