Occasionally we have conversations with people about MicroEssentials® S15™ and hear comments like, “it doesn’t have enough sulfur for canola.” While in certain cases this is true, we often reply with, “Or are you not putting on enough phosphate?” The reality is that we know what the approximate nutrient uptake and removal numbers are for canola:
Uptake: 58 lbs P2O5, 24 lbs S
Removal: 32 lbs P2O5, 10 lbs S
Uptake: 87 lbs P2O5, 36 lbs S
Removal: 48 lbs P2O5, 15 lbs S
With these figures, unless manure or some other major P source has increased your soil P to the point of wanting to actually draw it down, MicroEssentials S15 analysis is perfectly suited to canola in western Canada.
The slow release elemental S portion helps mitigate potential leaching loss in season, so no matter what your yield environment, in theory there should be 4-5 lbs of additional S to be available in the following season if you match P removal. This is why 100 lbs/ac of MicroEssentials S15 has performed so well on many western Canadian farms. But now many farms are far surpassing 50 and even 60 bu/ac, so to keep up with P removal we really need to be looking at higher rates of MicroEssentials, which we can be confident will always supply a proper ratio of P:S for canola.
For the exceptions where you need more sulfate, AMS (21-0-0-24), ATS (15-0-0-20), and K-Mag (0-0-21.5-21 + 10.5 Mg) are all very good sources of immediately available sulfur. AMS and ATS should rarely be placed in the seedrow, but K-Mag has the benefit of being a very low salt index, NH4-free source of sulfate, so can often be safely applied in the seed row if needed (and it also supplies K!)
For more information check out www.mossaicco.com.