Any investment in inputs is significant, so the clever farmer will want to maximise its return. But how do you maximise the amount of nutrients your crops actually benefit from?
Last year’s soil analysis data showed that 96.5% of UK soils were below sufficient levels for sulphur. On top of that, sulphur is another nutrient that is prone to leaching so as the wet weather continues it’s essential that we address this sulphur deficiency.
Agronomists now consider sulphur to be the second most important nutrient as it’s not only essential for plant metabolism, but it plays a vital role in nitrogen uptake.
If you’re growing wheat, a sulphur deficiency will result in your crops taking on a bright chlorotic, yellow-green colour which can be seen at the youngest leaves first. Growth will be stunted and the number and size of grains will be reduced. Ultimately yield and quality suffer.
But sulphur deficiency also impacts nitrogen use efficiency. Essentially, with less sulphur available, your crops will not be able to absorb as much nitrogen as they could. So if you ignore the need for sulphur, you’ll be reducing your fertiliser’s return on investment.
If sulphur improves nitrogen use efficiency, it also reduces nitrogen losses which is not only good for the grower and crop but also for the surrounding environment.
Another worrying statistic from soil data is that 52.4% of soils are below 5% of organic matter. Why is this important? Lower organic matter means lower nutrient retention, so applying organic material should be part of your solution to nutrient loss.
Organic manures are also likely to contain some sulphur but levels are variable and analysis should be sought to know exactly how much sulphur you’re getting. Also, you won’t be able to completely rely on organic manures as the sulphur it contains will not be in the sulphate form and so will have to go through a conversion process before being available to your crops, making it available potentially later on in the season.
As always, remember that precision is key so ensure you know the analysis of any organic materials that you plan to apply, enabling you to create an efficient nutrient management plan.
Another characteristic of soil health that sometimes gets overlooked is soil pH. Last year’s soil data showed that over 52% of soils were below the optimum pH range for arable crops. If your soil is not around pH 6.5 then it will affect nutrient availability. You will then be facing a higher fertiliser bill or a drop in crop yields.
We are just about to go into a period of increased sulphur demand for a growing wheat crop and typically we know that half of the crops’ sulphur needs are missing.
Because sulphur is prone to leaching, Yara has always recommended a little and often approach to applying sulphur. After spreading your early season NPKS at the mid-tillering stage (likely February time), we’d recommend following that up at GS 31-32 (March time) with a product like YaraBela Axan which has the nitrate and sulphate your growing crops need.
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