Fertilizer: Safe-seed placed rates

April 29, 2020 – Issue 7

The recommended practice for canola is to place no more than 20 lb./ac. of phosphate (40 lb./ac. of MAP, for example) with the seed and put all other fertilizer outside the seed row. The reasons are explained in this section of the Canola Encyclopedia.

You may also enjoy this article “What should you do about phosphorus rates?” from the March 2020 Canola Digest. Here’s an excerpt:

… A research project led by [Cindy] Grant and repeated at various locations in Canada showed that going from 20 lb./ac. to 40 lb./ac. of phosphate (liquid or dry formulations of ammonium phosphate) in the seed row thinned stands by about 20 per cent. Adding 20 lb./ac. of sulphur as ammonium sulphate (dry) or thiosulphate (liquid) took it down by another 20 per cent or so. (These results are highlighted in the article “Product and placement”, which is in the 2013 Science Edition.)

“Canola can still yield well with a 40 per cent drop in stand – as long as seeding rates were high enough to keep plant counts above five per square root – so the real management decision is whether the reduced seed return on investment is offset by improved fertilizer logistics,” [Warren] Ward says. …

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