Another difficult season has thrown farmers a curveball. Although it's only August, the harvest is mostly in across England and Wales with yields, quality and straw condition all affected. Yet as one season ends, growers are already turning their minds to the next, and oilseed rape looks set to feature more heavily in autumn plans. James Willis, one of Yara's Area Managers, explains how to establish OSR during the ongoing drought.

OSR. A crop making a comeback

Since the Europe-wide neonicotinoid seed treatment ban (and the cabbage stem flea beetle (CSFB) pressure that followed) OSR coverage has fallen sharply over the last decade. But now the crop is edging back into rotations, with a new impetus driven largely by economics. 

"Oilseed rape has been trading at around two and a half times the value of feed wheat," says James. "Andersons estimates cropped area rose 22% this year compared with 2025 and this is a trend we expect to continue as domestic demand and pricing hold firm."

Even so, coverage remains less than half the 750,000 hectares grown at OSR's peak. With the lack of break crops and new chemistry to tackle grass weeds in cereals, growers are increasingly looking to bring OSR back into the rotation, because this also offers more weed control options through the use Kerb or Centurion Max for example. 

Moisture is more important than the date

With the harvest over, growers would usually be planning to put winter OSR in the ground. But this year, with ongoing drought conditions, James' advice is to hold off.  

"Thankfully some areas of England and Wales have seen some rain recently," he says, "and this will benefit the preparation of a stale seed bed. But we're still in need of a good few days of steady rain to meaningfully increase the moisture OSR needs to get going."

As well as moisture, OSR establishment is strongly influenced by slug activity and CSFB pressure and there are many establishment systems that aim to manage these challenges. Whichever establishment method growers choose, James says rapid and even emergence should be the aim, with a target of 25 to 40 plus plants per metre square in the spring. "Robust, healthy plants are better able to withstand the pressures from slugs and CSFB and a full and enclosed canopy helps out-compete weeds and deter pigeons." James explains. 

To achieve this, good seed-to-soil contact in a fine firm seedbed conserves moisture and enables rapid emergence and early growth. In recent seasons drilling into dry, dusty seedbeds has led to slow, uneven establishment and has given CSFB an easy target. James' advice is to drill slightly ahead of rain rather than after it, minimising moisture loss through cultivation, and to keep the soil moist once germination begins to avoid a false start. "So ideally you know there'll be some rain in the forecast following drilling." He explains. "Patience is key. You want to set the crop up for success early on, so ensuring you're drilling only into the best conditions you can is important."

Timing the pest and disease risk

Recent work into CSFB suggests their emergence is perhaps later than previously thought. This has prompted some growers in high-burden areas to drill in late July or early August, aiming for larger, more developed plants by peak grazing. And this year's dry conditions also seem likely to push CFSB emergence further back. But James notes the trade-off: earlier drilling can increase stem larval pressure, as more eggs are laid on established plants, while crops drilled before mid-August are also more exposed to cabbage root fly.

Another consideration, where brassicas such as OSR are included in the rotation as game cover, forage crops or environmental planting mixtures, is club root. This favours warm, moist, acidic soils and is a growing concern in Scotland and in some regions of England and Wales. With no chemical controls available, James says other methods will need to be in place to manage it. 

"Longer rotations, soil testing and resistant varieties can help." He says. "But as club root is a diverse pathogen, varietal resistance may not always be effective 100% of the time." 

Feeding the crop from day one

With a small root system at establishment, OSR can quickly exhaust the nutrients immediately available in the soil solution, so early nutrition matters. James recommends having the fertiliser ready: a starter fertiliser applying 30kg N/ha broadcast (in NVZs, applied by the end of October), or 20–25kg N/ha where fertiliser is placed through the drill. 

Phosphate and potassium are equally important at this stage, building root and shoot growth that helps the crop access water and nutrients deeper in the profile later in the season. Phosphate supports protein synthesis and energy transfer and is best placed at drilling given its poor soil mobility – moving less than a millimetre through the soil. Potassium regulates water, acting as a natural antifreeze that improves over-winter survival and limits transpiration loss during dry periods. 

"It's important not to delay this application until after emergence under a wait-and-see approach," James cautions, "as by then soils have started to cool and growth rates are dropping, reducing the benefit of the starter fertiliser."

For growers looking for a solid starter fertiliser, James points to YaraMila ACTYVA S (15.6-14.6-14.6 + 6.5% SO3). This supplies immediately available N, P and K, including essential phosphate for extended availability at lower risk of fixation, plus, critically, sulphur to support nitrogen utilisation. 

Yara Multi 18-27-0 offers a liquid option suited to automatic applications. As root and shoot growth increase, so does demand for micronutrients, and James suggests an application of YaraVita Brassitrel Pro at the four to six leaf stage. This multi-nutrient product supplies calcium, boron, magnesium, molybdenum and manganese. Molybdenum supports nitrogen metabolism, while calcium and boron promote strong cell walls that help mitigate pest damage.

Patience and not panic

Despite this year's variation in drilling dates, James's advice remains consistent. Hold your nerve, wait for moisture and have your fertiliser plan ready to go the moment conditions allow.

"In some parts of the UK at the moment, ground is so hard and dry it's even creating additional wear on cultivation equipment." He says.  "And letting seeds lie around the dry seed bed for weeks on end does nothing for their viability. The key is to set the crop up for success early on. Only drill OSR now if conditions are appropriate for rapid, even emergence and consider how moisture will be conserved and the appropriateness of your establishment system, as well as the importance of early crop nutrition. Don't manage the crop on the assumption of failure. A balanced NPKS compound is ideal for starter fertiliser, ensuring the correct analysis is delivered evenly wherever it lands."

Anyone wanting further guidance can contact their local Yara area manager or visit the Yara website.