The tail end of Hurricane Katia and heavy showers since have not helped the already slow potato harvest in the east of Scotland. Torrential rain has left all but the freest draining land at field capacity although “above average levels of sunshine for the east of Scotland” are predicted for the next month. So let’s hope the forecast is right!

 

Tuber numbers are generally above average. Coupled with little sunshine in the later part of the season, this has meant late burn-off for some seed and ware crops. Desiccation has generally worked well but some indeterminate varieties are sometimes requiring a third application to prevent regrowth.   

 

Waterlogging is the major problem with most fields having some soft rot patches. Boxes from these areas and wet tramlines need to be kept separate. For seed growers, positive ventilation is going to be critical to reduce erwinia bacteria levels and sufficiently dry the crop going into store. Ware growers need to make sure fridges and fans keep air moving during store loading and the front of the fridge is kept full of boxes to prevent short circuiting of air.

 

Powdery scab is now showing in high-risk fields and varieties, with control in seed crops by fluazinam less effective than previous seasons. 

 

Slugs are also proving a problem in susceptible varieties as numbers have not decreased during the wet summer even with intensive control programmes. If harvest is going to be delayed, a further application post desiccation may be justified providing harvest interval, maximum total dose and metaldehyde stewardship is complied with. 

 

Planning for harvest and store loading is going to be critical this season. Know the quality of field before harvest and how you are going to handle it to maximise quality and minimise risk.