Soybeans – Planting and Fertilizing a Deer Food Plot
Q: We are planting soybeans in a food plot for deer. The seed company recommends 0-70-120 for fertilizer. What does this mean and can we mix it ourselves?
A: Since fertilizer dealers in different parts of the country sell different analyses of fertilizers that contain different amounts of nitrogen, phosphorus, and potassium, the recommendation is telling you how many actual pounds of nutrient to apply per acre.
The seed seller is giving you a “typical circumstances” recommendation. You would be much better off to have a University of Georgia soil test done so that you know how much lime to apply as well as fertilizer. Good soil pH is critical for soybean yields.
Here’s the UGA soil test page for summer deer plots
Since soybean plants produce their own nitrogen, you don’t need any nitrogen in your fertilizer. That explains why the first number is “0”.
Soybeans do need phosphorus and potassium. This explains the “-70-120” part of the recommendation.
Since the last number (120) is more than 100, I can see that this recommendation wants you to use actual pounds per acre rather than a percentage analysis.
( 13-13-13 is a typical “percentage” analysis. This particular kind of fertilizer contains 13% nitrogen, 13% phosphorus and 13% potassium. A 100 lb bag would actually contain 13 lb. of each nutrient.)
A recommendation to use 0-70-120 means they want you to apply 70 lb. of actual phosphorus per acre and 120 lb. of actual potassium.
Phosphorus is sold as superphosphate (0-18-0) or triple super phosphate (0-46-0). So you’d need 388 lb (70 divided by 18 times 100) of 0-18-0 or 152 lb (70 divided by 46 times 100) of 0-46-0 per acre.
Potassium fertilizer is usually sold as 0-0-60. You’d need 200 lb (120 divided by 60 times 100) of 0-0-60 per acre.
The simplest option is to march into your local feed/fertilizer store and tell them you are planting soybeans for deer. Most professionals will have the exact fertilizer you need for your plot.