Applying the right nutrition following autumn establishment can be just as vital to a crop’s potential as timely spring applications, and choosing the right nutrients to support nitrogen uptake, will ensure a stronger crop ahead of the winter.
“With the second wet autumn in a row, sulphur levels will be at an all-time low due to it being a very mobile nutrient prone to leaching,” says Toby Ward, nutrition agronomist at Origin Fertilisers.
“Applications to address deficiencies will be essential to maximise crop potential. Sulphur is fundamental for protein formation and has a key function in improving crop quality. Crops with a high nitrogen requirement, such as milling wheat, will have an increased sulphur need, as its presence helps increase nitrogen use efficiency. It should be part of any prescription nutrition plan from the start, and understanding how sulphur can be applied will offer greater flexibility.”
Although growers may focus on straight nitrogen supply for the spring, if this is combined with all the farm’s sulphur requirements, it doesn’t offer flexibility for post drilling autumn applications. It is worth considering additional options when assessing how to apply sulphur.
“Sulphur is often considered a secondary nutrient to nitrogen, but there is evidence to suggest its role is just as important. Growers should be clear that they don’t have to be tied by combined nitrogen and sulphur products, as sulphur fertilisers such as Polysulphate can offer wider application flexibility and additional nutrition.”
Extended availability
Sulphur has the greatest efficacy when it is available little and often alongside nitrogen throughout the season, but it is worth noting that a late application of a sustained release sulphur fertiliser will still enhance the uptake of nitrogen as opposed to no application at all. Polysulphate offers growers a different option to traditional nitrogen and sulphur fertilisers as it has an extended release period and contains several secondary nutrients, as Toby explains.
“Polysulphate will not only help crops access mineral nitrogen in the soil immediately, but its prolonged release period of 55 days will support nitrogen uptake on bright days in the winter and into early spring. Furthermore, the presence of magnesium, calcium and potassium within Polysulphate means growers are applying other vital nutrients with each application.”
Magnesium and calcium support stronger rooting to increase plant resilience during the winter and the improved root structure allows the crops more access to nutrients. Potassium is integral for cell development and its presence helps build strength ahead of the winter and improves disease resistance. Polysulphate is also certified for organic use, allowing additional options for growers who don’t apply nitrogen.
“The inclusion of magnesium and calcium means plants will develop bigger root structures before the winter. Growers can also benefit from early spring applications on frosts as Polysulphate can be applied at the start of the year to maximise any retained soil nitrogen. It will then be in the soil ready to support spring applied nitrogen due to the extended availability.”
Sulphur quantities
Defici
encies will appear in every soil and will be the limiting factor to crop production. However, the growers getting crops off to the best start following establishment will be those applying sulphur to maximise any residual nitrogen that has remained in the soil.
A 100kg application of Polysulphate would supply around 48kg of SO3 to the growing crop over the course of the season – enough for most cereal crops according to RB209.
When considered alongside the three additional nutrients in Polysulphate, there is greater value to each application. Toby says this is an essential consideration when purchasing nutrition.
“The presence of the three additional nutrients in the same bag means the benefit of a Polysulphate application is much greater than straight sulphur. It represents a greater return on investment than traditional products and helps to maintain nutrient levels within the soil. A FACTS qualified advisor can indicate the best timings for a Polysulphate application following drilling to maximise the nutrition,” concludes Toby.
