Improved prospects for harvest 2025 as OSR makes a strong start

Reduced cabbage stem flea beetle pressure and a relatively kind winter have seen all 13 of Bayer’s 2024/25 oilseed rape farm strip trials survive through to spring, with average establishment across all varieties in the trials standing at 82% and minimal plant losses over winter.

Only two trials, at Rougham in Suffolk and Inchture in Perthshire, were drilled before 21 August, with the drilling date window across all sites ranging from 7 August in Suffolk to 18 September in Shropshire.

This season’s trials see six mainstream Ex hybrids including DK Excited, DK Exstar and last season’s newcomer DK Excentric grown alongside coded varieties from the DEKALB development programme, a HOLL variety and a ‘control’ of LG Aurelia. The trials are grown under commercial farm regimes at sites across the country.

Bayer trials manager Richard Williams notes that while there was some evidence of cabbage stem flea beetle scarring in earlier drilled crops, and larvae could be found during the spring assessments conducted in late March and early April, CSFB pressure was generally low, and plant numbers at the spring restart were comfortably within the 30-35 plants/m² optimum.

“Crops haven’t been eaten like they were last year, when we saw some of the strip trials taken out by CSFB larvae,” says Richard.

“In the spring counts we'd got between 30-34 plants/m², which is spot on, especially when you consider that the DEKALB varieties branch really nicely lower down. Plant survival rate is between 60%-68% so where we’re planting at 50 seeds/m² we’ve got plenty of plants.”

Crop development before winter (DBW) scores once again highlight the autumn vigour of the DK hybrids, with an average score of 5.2 on a scale of 1-9 (where 9 is fastest development).

High yielding hybrid DK Excentric, new to the market in 2024, was right on the average score at 5.2, while pipeline varieties CWH596, with triple phoma resistance, and clubroot + TuYV resistant DMH585 both scored 5.5, highlighting their exceptional autumn vigour.

Currently awaiting National Listing, both varieties were equally quick out of the blocks this spring, with CWH596 - which is seen as a potential replacement for the highly consistent DK Exsteel, an AHDB Recommended List newcomer back in 2019/20 - earning a spring restart score of 5.7 and DMH585 scoring 5.5 on a scale of 1-9 (where 9 is earliest).

Rapidly earning a reputation as a go-to variety when conditions are less than ideal, DK Excentric is also proving to be a standout variety in terms of its canopy structure, adds Richard.

“It's got huge leaves; it's got great ground cover. It really is a good looking variety,” he says.

Reflecting on the contrast between last spring’s wet conditions and the dry, warm weather this spring, he adds that oilseed rape crops are on the whole in much better condition this season.

“In 2024 we had 25% of sites with average spring plant populations of fewer than 30 plants/m²; this season we've got nothing below 30 plants/m².

“This year crops have more anchorage, in contrast to last, when there was a lot of stem leaning and plants were poorly rooted, with wet feet well into spring.”

Those growers who have stuck with oilseed rape have mostly had a good season so far and are on course for better yields compared to last year, suggests Richard.

“Oilseed rape is still the best break crop ahead of a first wheat and with the uncertainty over SFI, I really do think there is an opportunity for growers to reconsider its place in the rotation this autumn, but it has got to be grown professionally,” he says.

Table: Overall performance 2024/25 compared to a similar mix of varieties and sites in 2023/24

Source: Bayer