Mo once every four years across the program, or As for wheat. For maximum effect nitrogen needs to be available to the canola plant at the beginning of stem elongation. There is no consistent benefit to delaying Nitrogen application. Therefore it is a realistic option to apply all nitrogen at seeding if this is an easier strategy. The only requirement of the Sulfur source is that it is in a form that is readily available to the plant.
Elemental sulfur is only effective when it is in the powdered form.
Fertiliser toxicity is a very real risk when high rates of nitrogen are drilled close to the seed. The risks increase when seeding with knife points, sowing into dry soil and increased row spacing. Less if the soil is dry or at wider row spacings. Regular soil testing is strongly recommended to further refine the decision for individual situations. The term pH means hydrogen ion concentration in a solution.