You can save money on fertilizer six ways in 2009, says Ron Gelderman, SDSU Extension soils professor.

1) Know both the need for added N and the rate of N to apply. "Conducting a deep nitrate-nitrogen soil test, at depths of two feet, will determine additional N needs. Finding out how much available nitrogen you already have in the soil is like getting free fertilizer."

2) Reduce N rates. "Several studies show that modest reductions – cutting rates by 15 to 25 pounds per acre – are prudent now for corn and wheat. Using nitrogen credits for legumes and manure is yet another way to save on N input expenses."

3) Account for N credits from soybeans. "The average nitrogen credit from a previous crop of soybeans or field peas is 40 pounds per acre, and can lead to savings of more than $20 per acre.

4) Use manure credits. "If manure is available, make sure to credit the available and potentially available N from this source. Depending on purchase, hauling, and spreading costs, this source can be an excellent value for your crop needs." Manure works as well or better than fertilizer nitrogen when applied at recommended rates.

5) Time N applications to reduce losses. "Applying N just before planting or side-dress, in most cases, limits the amount of time for potential loss to occur. No-till is an exception. N should be broadcast on the soil surface in early spring when temperatures are lower. This allows for more time for rainfall to occur which reduces potential gaseous losses."

6) Consider nitrogen rates in other types of fertilizer, such as phosphate. An application of 60 pounds of phosphate as DAP, (18-46-0) adds 23 pounds of N per acre, at a value of about $13.

"Using realistic yield goals, planting more legumes, and pricing different N sources can save on your fertilizer budget as well," Gelderman says.

Source: SDSU AgBio Communications Unit