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Are you considering taking a break from oilseed rape next season? Why not instead consider how you can put the profit back into this crop before it becomes history on your farm.

Having been central to rotations, the country’s favourite break crop is falling out of favour. From a high point of about 700,000ha, the 2016 oilseed rape area in England is the lowest since 2009, down 10% on the previous year at 548,000ha.

Behind this dramatic fall from grace are a number of factors, including a drop in profitability. Or to put it another way, yields are down, costs are up and crop establishment has become much more challenging, summarises Chris Bean, technical director of Zantra.

See also: How to extend greening to improve oilseed rape yields

“Remember that oilseed rape used to be as important as wheat in terms of potential returns,” he says. “But the high value of the crop meant that it was being grown too frequently in the rotation, either every other year or one year in three, which is too close.”

As a result, cheaper and faster drilling methods had to be adopted in order to get it all planted. This made it harder to get the best from the crop and created challenges with both weed and disease control, all of which have proved difficult to overcome, he notes.

“We’ve also seen a ban on insecticidal seed treatments and the introduction of the three crop rule, leading to greater areas of other crops in the rotation, particularly pulses, often at the expense of rape.”

So what, if anything, can be done to improve its prospects?

“It’s not all bad news for oilseed rape,” stresses Mr Bean. “It may not be the cash cow it once was, but it still one of the break crops most likely to show a positive gross margin.

Varietal advances

“It is also harvested early,” he adds. “Add this to the exciting varietal technologies that we have for this year, and the crop starts to look a bit more interesting.”

He highlights new lower biomass varieties, which are easier to manage and harvest, and are increasingly coming with other characteristics, such as less pod shatter and shorter flowering periods.

“There’s also Clearfield [herbicide tolerant], which has been under exploited to date. The varieties are changing and weed control in oilseed rape is becoming a big issue.”

As the post-emergence herbicide options are very limited, he believes Cleranda (imazamox + metazachlor) which is used only on Clearfield varieties could have a significant part to play.”

According to Andrew Bourne of Kent-based T Denne & Sons, growers who are sticking with the crop should look at ways of maximising output and minimising risk – some of which can be achieved by selecting the right variety in the first place.

“Start by looking for the varietal characteristics and traits that will help you achieve these twin aims,” he says. “Lock into a premium if you can and opt for reliable, consistent performance.”

He adds that when oilseed rape prices are hovering at or below the cost of production, variety choice is important. “One size fits all is no longer appropriate. There are choices that are less susceptible to the vagaries of the season, and to management challenges on difficult sites.”

Mr Bourne has a long list of variety criteria (see box). “Seed yield is a key factor, but it is probably the most variable part of oilseed rape production, with a variety’s position on the Recommended List and its on-farm performance often at odds. So selecting varieties for reasons other than yield will help give more consistent returns.”

Also high on the list is end market, as there is a valuable premium on offer for the specialist oils suitable for the human consumption market. However, growers must appreciate that high oleic, low linolenic (Holl) varieties are only available with a specific Holl crushing contract.

Establishment characteristics and spring development are next. He mentions good early and late autumn vigour as important for certain situations, but accepts that growers won’t find this information on the Recommended List.

“Varietal vigour differs greatly between varieties in the autumn – both for hybrids and conventionals – so match the variety to your site and drilling date.”

“Spring development is also important. Where you have early growing sites in the spring, faster developing varieties are best, but on a later site, a quick developing type will be compromised. You can find out more about vigour characteristics from your local seed specialist.”

Yield security

Security of yield at harvest is his next consideration, as harvest losses can be very high.

“Look for varieties which have pod shatter resistance, especially if you are growing it on an exposed site, and always consider the use of a pod sealant. There is nothing more frustrating than losing seed ahead of harvest.”

A spread of maturities across the farm’s oilseed rape acreage can also help to reduce losses, he adds.

Site concerns must be acknowledged and addressed, if possible. “You will know if you have low fertility, a weed burden or poor soil structure, just as you will be aware of a previous cabbage stem flea beetle problem or other pest problem. Managing or avoiding these situations is key to maximising output.”

Where there’s a cruciferous weed burden or weed control is proving too expensive, Clearfield oilseed rape might help, suggests Mr Bourne. “We’ve now got access to Clearfield varieties which suit a broad range of farm situations, so they do offer management opportunities.

“Varieties such as Imperial CL, with its good disease ratings and pod shatter resistance, mean that we’re not looking at compromises any more. It could allow you to get rid of some of the inconsistencies of growing oilseed rape.”

Disease and straw characteristics have improved with more recent variety introductions, he points out, with multi-site and polygenic resistance now on offer, as well as better late season standing scores.

“This is where it is worth drilling down into the detail. A higher light leaf spot or phoma rating gives you more flexibility, for example, and there are varietal differences in Verticillium wilt tolerances.”

He also notes that there is a new low biomass variety, CWH315D, up for recommendation later this year, with a height of just 124cm. “It’s very short and stiff, and offers easy crop management, particularly on high fertility sites.”

Oil content is another factor. For every 1% of oil over 40%, there’s a payment of £3.75/t with ex-farm contract values of £250/t – so a variety with an oil content of 45.9% brings in an extra £22/t.

“There’s a 2.4% range of oil contents on the East/West region Recommended List, giving a £9/t difference across the published scores,” he points out.

Variety traits and their value

Reducing growing costs while improving output should be possible with some of the most recent winter oilseed rape varieties, believes Will Vaughan-France of Dekalb.

“We’ve got some serious challenges to the crop in the form of climate, diseases and pests,” he says. “But some of these can now be overcome, or reduced, by growing the right variety.”

He points out that the arrival of better disease resistance ratings, 8/9s for phoma and 6/7s for light leaf spot, does allow savings to be made. “It usually means one less foliar spray has to be applied, and less expensive chemistry can be used.”

Extra leeway is also on offer from higher disease resistance ratings, he notes. “That can be more difficult to put a value on, but it takes the pressure off and allows spraying to be prioritised accordingly.”

Likewise, in-built pod shatter resistance has shown to have a 9% yield benefit, he adds.

Mr Vaughan-France also believes that a big step change has occurred with Clearfield varieties. “They are now conventional height varieties, with good yield and oil content, as well as other valuable traits.”

All the contributors were speaking at a recent “Putting the Profit Back into Oilseed Rape” open day in Kent organised by Zantra and T Denne & Sons