The Canola Council of Canada says canola growers tempted to cut back on fertilizer rates this spring may want to think twice.

“With canola prices having backed off of last spring’s highs and fertilizer prices remaining relatively high, growers might be tempted to shave fertilizer rates in order to reduce costs,” says Canola Council of Canada senior agronomy specialist John Mayko. “But canola growers who cut fertilizer rates may end up cutting their profits,” he said a release.

The council says that with higher than average canola prices, the opportunity for good returns is solid, but generous rates of nitrogen are needed for optimum returns, and phosphorus and sulphur also need to be at adequate levels.

“Today’s hybrids need adequate nitrogen to optimize the yield potential of the hybrid genetics,” says Mayko. “Although it is important to pencil out the potential profit situation for each farm, consider this: With canola at $9/bu and nitrogen costing approximately 60 cents per pound, for every 10 lbs of nitrogen applied, it will only take a three-quarter bushel gain per acre to recover that cost. Any yield above this gain is profit.”

The council says research by Agriculture and Agri-Food Canada and Westco Fertilizer indicates improved nitrogen response curves for hybrid varieties compared to open-pollinated varieties. That means for a given rate of nitrogen, hybrids typically yield better than open-pollinated varieties. However, to achieve the full genetic potential of current hybrids, greater amounts of nitrogen are required.

The council says phosphorus rates need to be adequate to ensure proper early season plant development. If growers have been applying moderate to high rates of P in recent years, an option is replacing some of this year’s phosphorus with JumpStart seed inoculant. Growers with low to medium P levels should apply at least 15 to 20 lb/ac of seed-placed or side-banded phosphate. This is important, especially in early seeding situations, when soils are often cool.

Sulphur (S) rates also need to be adequate across all areas of the field. Because of the inherent variability of S in many fields, an application of 15 to 20 lb/ac of S as ammonium sulphate is recommended, especially if S is only applied to a rotation in the canola year.

The council says soil testing is the only way to truly evaluate the nutrient status of a field and should be considered for making the right decision on  fertilizer this spring.