Drought and heat stress raise storage-quality concerns for UK potato grower

Rising spot potato prices are offering some relief to UK growers after two years of difficult trading, yet the summer drought and heat wave have introduced a new set of challenges: storage quality.

Cambridgeshire-based grower Steve Edgley cultivates 200 hectares of potatoes, primarily for the fish-and-chip market, and stores up to 5,000 tons across five facilities. Around 75 per cent of this year's crop was irrigated, although water restrictions affected some fields.

Storage infrastructure

The five facilities break down as follows:

• Two 500-ton bulk stores that hold potatoes until approximately February without additional sprout suppressants.
• Two 1,500-ton ambient-air box stores maintaining temperatures around 9 °C for longer-term storage.
• One 1,000-ton refrigerated store, also held at approximately 9 °C.

Treatment protocol under stress

Edgley applies maleic hydrazide for sprout suppression before storage. However, he notes that crop stress from the drought may have affected treatment uptake and skin set, increasing the risk of bruising and poorer storage performance.

Following curing and drying, the stores receive 1,4-dimethylnaphthalene (DMN) treatments every four to five weeks. As unloading approaches, Edgley switches to orange oil or mint oil because of their shorter holding periods. He reports that the facility is now running approximately 90 per cent Argos and 10 per cent mint oil.

Regular inspections determine when additional treatment is needed, and roughly 400–500 tons are dispatched weekly during the store-unloading phase.