Agronomy tips and advice for growers in the Midlands

1) Reduce oilseed rape establishment risk using Bayer varieties, tools and schemes

Lincolnshire grower Tim Lamyman broke the world record yield for oilseed rape last season after growing a crop drilled in September, showing that later drilled crops can be every bit as successful as early drilled ones.

One key for success is to choose a variety that has good autumn vigour, which all the DEKALB® varieties have. Bayer’s MagicTrap can also help provide insight into when to drill by monitoring for when peak cabbage stem flea beetle migration has passed.

If you choose a DEKALB® variety, you can also reduce risk by protecting it through our Establishment Scheme which will reimburse you through your seed supplier with £100/bag if there is a total establishment failure of blocks of 6ha or more. To participate, crops must be sown before 20 September and registered at cropscience.bayer.co.uk/dkestablishment by 30 September. Claims should be submitted through your seed supplier by 31 October 2025.

2) Good opportunity for stale seedbeds

An early finish to harvest, plus some rain in late July and early August, should help create decent opportunities for grass weed germination in stubbles post-harvest to spray off with Roundup®.

I’d consider running stubble rakes or shallow cultivators over stubbles to move the top couple of inches of soil to encourage germination of grass weeds. I would expect germination to be quite quick and there’s likely to be, as ever, a seed bank waiting to emerge.

With the early harvest, there could be an opportunity for two sprays of Roundup® ahead of autumn drilling but remember the key stewardship guidelines for glyphosate. With the discovery of resistance in Italian rye-grass those messages are ever more important to follow.

A key one this year will be to make sure that if a second application is made that any survivors from the first application are destroyed using some form of mechanical cultivation before a second spray is applied.

The usual advice around using the correct dose at the correct timing for species present remains crucial, plus paying attention to good application techniques – not going too fast, using the right nozzles and water volumes.

A stewardship trial in Lincolnshire where we trialled best practice weed management against poorer approaches on a field where black grass levels were low is highlighting that successful weed control with glyphosate is the backbone to overall performance.

Over the two years the trial has been running, the best results are always ones that have focused on good glyphosate applications. Where we had good overall weed management, but used poor glyphosate applications – either not ideal timing or cultivations – black grass numbers have increased.

3) September-drilled wheat likely to need two residual herbicides

After at least two seasons where autumn drilling has been compromised in some areas by weather, and another year where expectation is growing that there will be a deluge at some point to bring the yearly rainfall average back in line, it’s difficult to suggest to growers that they delay drilling wheat.

While that remains a more than useful tool to reduce the pressure on residual herbicides, it’s more a question of how much wheat will be drilled in September than if it will be.

There are things you can do to mitigate risk – good use of stale seedbeds as discussed, plus choosing fields with lowest grass weed pressure to drill first are sensible approaches.

But in many cases in the East Midlands, drilling in September almost certainly pushes you down a route where you are committed to spraying two applications of residual herbicides in the autumn.

I would suggest using Proclus® as the first application in the programme for a couple of reasons. First, Proclus® can only be used pre-emergence, so by not using it, you lose access to one of the more effective actives in the grass weed programme.

Second, it loses less efficacy in dry conditions than some other actives, making it more reliable. That’s because it is absorbed by the shoots as the weeds germinate and grow through the soil surface and relies less on soil moisture for efficacy.

Mixed with a metribuzin co-form, such as Alternator® Met, Cadou® Met or Octavian® Met or Liberator®, it makes a strong pre-emergence spray that can be followed up at peri- or early post-emergence with another residual application.

4) Protect potato crops from tuber blight

We’re rapidly approaching the end of the season for potatoes. Blight pressure has, thankfully, been low, but the dry conditions are causing some main crops to finish earlier than usual.

Blight inoculum usually will build towards the end of the season though, so using a product, such as Infinito® with good zoospore activity to help protect against tuber blight, will be sensible during the last part of the blight programme.

5) Check for Cercospora infections in beet

Weather in July and August has been somewhat favourable for Cercospora infections, with BBRO’s CropWatch sites finding spores at virtually all 20 sites at some point during July or early August, with active Cercospora lesions found at five sites.

Infection risk is only likely to have increased if the warm weather forecast for the second half of August also brings high humidity or showers.

Where continued protection into and beyond September is required, Caligula®, which is also strong on rusts as well as Cercospora can be used as a third spray in a programme from 1 September. This could well be a season where crops benefit from further treatment with slow growth during spring and summer perhaps delaying lifting for some crops.

6) Minimise groundkeepers in sugar beet

In sugar beet first crops will be lifted in September. If you’re growing a Conviso® Smart variety, remember to pay attention to groundkeeper management during harvest. Groundkeepers arising from Conviso® Smart varieties are potentially a source of weed beet issues in future years, minimising one of the benefits of using the technology.

Uneven, gappy crops or crops with variable crown heights that cause a compromise with harvester set up can increase risk from groundkeepers, so pay attention to harvester set up to minimise that risk.

If possible, plough after beet to bury tops at risk of re-growing, and if you don’t plough any areas used for temporary storage in the field, consider not cropping these areas next season and managing with glyphosate.

Where groundkeepers do emerge, remember ALS herbicides won’t be effective ones arising from Conviso® Smart varieties, so use hormone herbicides in cereal crops as an alternative treatment.

7) Look out for whitefly in brassica crops

After high pressure from aphids earlier in the season, look out for whitefly infestations on brassica crops, such as Brussels sprouts and calabrese in September.

If you start to see pest populations build, then consider using Movento®. The product works relatively slowly over a period of days, when the plant vascular system is actively transporting the product, and the pests are actively feeding.

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Alternator® Met, Cadou® Met and Octavian® Met contain diflufenican, flufenacet and metribuzin. Caligula® contains fluopyram and prothiconazole. Infinito® contains fluopicolide and propamocarb. Liberator® contains diflufenican and flufenacet. Movento® contains spirotetramat. Proclus® contains aclonifen. Roundup® contains glyphosate.

Alternator®, Cadou®, Caligula®, Conviso®, DEKALB®, Infinito®, Movento®, Octavian®, Proclus® and Roundup® are registered Trademarks of Bayer. All other brand names used are Trademarks of other manufacturers in which proprietary rights may exist. Use plant protection products safely. Always read the label and product information before use. Pay attention to the risk indications and follow the safety precautions on the label. For further information, including contact details, visit www.cropscience.bayer.co.uk or call 0808 1969522. © Bayer CropScience Limited 2025