Building in resilience when establishing winter crops

EXPERT VIEW

Soil health and nutrient availability are key to a good start for crops, says Simon Fox.

The long, hot summer makes it easy to forget just how harsh winter can be for autumn-sown cereal crops.

In previous seasons, there has usually been the fallback of playing catch-up in the spring. But with nitrogen supplies limited and prices at sky-high levels, this option is unviable for many growers going into 2023.

That said, there will be considerable nutrientsleft in the soil from the previous crop. And with soils still warm in the autumn, we must maximise the use of these reserves rather than letting them leach out over winter.

One strategy is to achieve maximum germination and the establishment of strong, healthy, resilient plants going into winter. To achieve the best results with autumn planted crops, the to-do list can be broken down into the following action points:

Soil sampling

This season, soaring farm input costs should make soil sampling a no-brainer. When you’re looking to maximise the financial and environmental efficiency of your inputs, it is important to understand nutrient availability of the soil

This is both in terms of what is there in crop-available formulations, and what is locked up in the soil and unavailable. This baseline information can then be coupled with yield and quality forecasts to devise a plan for the crop.

It is possible to produce a plan to bridge the nutrient gap to ensure the crop has all it needs to achieve optimum growth in terms of a growth stage strategy for micro and macro nutrients, biostimulants and fertilisers.

Soil preparation

For winter cereals and oilseed rape, this gives roots less resistance moving through the soil. It allows them to travel further, enabling them to make use of soil-stored nutrients and helping to rectify possible compaction issues from previous seasons.

Oilseed rape can be direct drilled and winter cereals planted using minimum tillage operations where compaction isn’t an issue – both systems which have the additional advantage of preserving valuable soil moisture after the dry summer.

Using minimum tillage techniques, also helps to maintain or improve soil structure, reducing the release of carbon into the atmosphere and reducing the chances of soil compaction.

Germination rates 

High germination rates can be achieved with lower seed rates in crops drilled during September and early October. Typically, wheat crops require 150 day degrees celsius from sowing to emergence.

This can be as little as 11 days in September and around 25 days for November sown crops. Those that emerge in early autumn have time to become established with good root systems before the harsher winter weather sets in.

Increased root formation

Throughout the season, there is a tendency to focus on the crop above ground. But the reality is that post germination and throughout early autumn, we should focus on establishing a strong, numerous root system.

Good root systems will encourage a consistent and uninhibited flow of nutrients to the crop in the coming spring – maximising the utilisation of any nutrient reserves in the soil left from the previous crop before they are leached out over winter.

The vigour and quality of germination, establishment and root formation can be influenced by using biostimulant products at, or soon after, sowing. Specific combinations of organic acids can promote root growth – and aid nutrient uptake.

As crops descend into dormancy over the winter months, roots then continue to thrive and develop, creating an extensive nutrient transport system.

 This puts the crop in a good state for further growth and nutrient uptake when day length and temperatures increase.

Stronger healthier plants

After germination and before winter dormancy, it is important that crops should be evaluated for minor and micronutrient deficiencies. Depending on soil type, the most common deficiencies are magnesium, manganese, sulphur, copper and zinc.

At a time when input costs are at an all-time high, establishing a healthy, hardy crop has the advantage of maximising input efficiency and building in resilience to whatever extremes the winter months deliver.

Taking the first steps towards a resilient winter crop starts with knowing your soil – and post-harvest is the ideal time undertake an extensive soil analysis and start your OptiYield journey to better crop performance, more profit and greater sustainability.

Simon Fox is director and founder of Emerald Research. For details, visit www.emeraldresearchltd.com.