Features Agronomy Fertility and Nutrients
Soil test now to get the most from canola in 2009

October 14, 2008

"Successful fertility planning for next year’s canola crop starts with proper soil testing this fall," says Canola Council senior agronomy specialist John Mayko. With record high fertilizer prices, it is more important than ever to get a good handle on nutrient levels in the soil before deciding on blends for next year.

"The key to getting useful results is sampling at the proper time – once soil temperatures drop below 7ºC," says Mayko. At this temperature threshold, microbial activity slows significantly and subsequent nitrogen mineralization will be minimal. Fall soil test results will be most reflective of spring nutrient status if cores are taken after soils have cooled to below 7ºC.

Mayko advises sampling down to 24 inches but reminds growers to keep the top six inch sections of the cores separate from the lower depths. The reason? Sampling to 24 inches will provide the most accurate numbers for nitrogen and sulphur because these water mobile nutrients can be found deeper in the soil profile, particularly in high moisture areas. However, the upper six inch fraction will provide the best indication of available levels of less mobile nutrients like phosphorus and potassium.

With fertilizer being such an important input with canola, it just makes sense to use soil tests when planning your fertility regime.

"Experience has shown that by feeding canola properly, you will maximize yield potential and increase the stress tolerance of your crop. Combining soil test results with local information on soil moisture will help you optimize your canola nutrient package to maximize profits next year," says Mayko.

For more information on proper soil sampling and understanding soil tests, visit:

http://www.canolacouncil.org/canola_resources/product38.aspx