Options for Fertilizing Pastures
Is nitrogen fertilizer too expensive for pasture? The answer depends on how well you manage your fertilizer applications and grazing.
After adding nitrogen to your pastures in past years, did your grass grow well in April and May, get stemmy in June, and turn brown and become matted by August with little green material for grazing. If your pastures often are overgrown in spring and run out in summer, change fertilizer timing to get more grass when you want it.
First, don't fertilize all your pasture right away. You're stimulating more spring growth than your cows can eat. Fertilize half or three-quarters of your pasture now.
Be sure, though, that the unfertilized area is fenced off from the rest of the pasture. Graze this unfertilized pasture first so that it's finished by mid-May. Then check the weather and soil moisture in your area. If you think there will be enough moisture for good regrowth, fertilize this previously unfertilized area. Let it regrow for six weeks or longer for grazing in July or August.
If it's dry in mid-May and prospects for regrowth are poor, don't apply any more fertilizer. You still will have produced about as much pasture growth as if you had fertilized everything to begin with, but without spending as much.
Extension Forage Specialist