Cultivation after harvest

Could Last Year’s Cultivation Be Paying Off?

Calling All OSR Growers in the UK

As we head further into the OSR season, results from the national cabbage stem flea beetle (CSFB) larval survey point to generally lower larval pressure across much of the UK this year. Could it be a coincidence, or might the proactive steps we encouraged last season be starting to make a real difference?

Last summer, United Oilseeds urged members to carry out a light post-harvest cultivation on recently combined OSR fields. This advice was grounded in promising research from Colin Peters and the NIAB team, showing that disturbing the top few centimetres of soil after harvest could disrupt the CSFB lifecycle during the pupal stage, potentially reducing adult emergence by 50–90%. Cabbage Stem Flea Beetle (CSFB) research

We weren’t certain it would work everywhere, but the technique was straightforward, low-cost, and worth trying. And now, with fewer CSFB reports, the question has to be asked: could your cultivator have made a difference?

Part of a Bigger Picture

This practical strategy is one of the OSR Reboot Top 10 recommendations for integrated CSFB management. And it’s not just us who see the potential: shallow post-harvest cultivation is also one of the core areas of focus for the proposed new AHDB 4.5-year funded CSFB research project, which is due to get underway soon.

We've recently captured footage of light cultivation in practice, showing just how easy and effective this action can be, whether using a straw rake or shallow discs. View our recent video below and see how fellow growers are putting the science into practice.

In practice, it’s important to ensure you are moving 100% of the soil, not just turning 25% of it over on to the rest. This may require some trial and error with your equipment, but following a pass, use a spade to check whether 100% of the surface soil has been disrupted.

What Can You Do This Harvest?

If you're harvesting OSR in the coming weeks, consider repeating or trialling this approach. The current research suggests disturbing the top 3–5cm of soil as soon after harvest as possible. Whether you're cultivating your own stubbles or supporting neighbours’ fields, the benefits may extend beyond your own boundaries.

Could this simple step be part of the reason we’re seeing less CSFB this season? It’s too soon to be sure, but the signs are certainly encouraging.