Agronomy Advice | Micronutrients make a difference to oilseed crops

Adequate nutrition including both macro and micronutrients has always been important for oilseed crops, not just to ensure successful establishment but to set the ultimate yield potential of the crop, so micronutrients shouldn't be overlooked when building an oilseed crop nutrition programme.

Farmer and Yara Agronomist in a oilseed rape field reviewing the crops

A deficiency of any single nutrient is enough to limit yield

Over the year’s trials have also taught us the importance of getting these micronutrients on at the key timings, before any deficiency starts to appear. A preferable mindset is to think about ensuring sufficiency of supply. This is where the importance of historic farm data comes into its own, enabling proactive decisions to be made. If such data is not available, an alternative proactive approach can be taken by using crop-specific products that have been designed to deliver the key nutrients for crop growth and development.

You may ask how do we know what are the key nutrients for each crop? The answer here again lies with research data and knowledge that has been conducted to identify them. Yara, through its research facilities in Pocklington, York, runs a screening process through nutrient specific trials to prioritise nutrients according to their impact on crop growth and development. Once these are established then crop-specific products can be formulated to deliver enough quantities of these specific nutrients. Crop specific products are an ideal way of starting your micronutrient strategy in the autumn, especially with the earlier drilled crops (e.g. wheat and oilseed) that will be starting to develop those all-important yield components during the autumn/winter months.

For the oilseed crop to be resilient and come through the winter months the target should be to have 6 - 8 true-leaves, with a root head diameter of >5 mm and a shoot length of around 20 mm. During the autumn the potential number of flowering branches is also set with flower initiation taking place from November. With so much of the yield potential being generated during this period, the autumn crop nutrition plan is critical. YaraVita Brassitrel Pro with its combination of nutrients including Boron is an ideal solution for this growth period.

Yara UK Brassitrel Pro trials

Trials have again confirmed the extra yield that can be obtained from the inclusion of key micronutrients in your nutrient strategy. Over the last five years (2016-2021) the average extra yield was around a third of a tonne per ha following the application of Brassitrel Pro.

The 2020 response was the greatest at 0.66 t/ha when applied sequentially with 3 l/ha in the autumn and spring but the long term average consistently gave a yield response.

Micronutrients are not just for high yield potential crops

Are micronutrients only worth investing in on high yielding crops? This is another question we often get. Whether an oilseed crop is 1 t/ha or 5 t/ha, 0.27 t/ha is the same value irrespective of yield. There is an argument that every extra bit of yield that can be achieved on a low yielding crop helps to spread the fixed costs that are higher per tonne on a poor crop!

It is also worth thinking about the return on investment in micronutrients. Based on current crop and product prices, if applying Brassitrel Pro at 3.0 l/ha, only an additional 23kg per ha are required to cover the cost of application.