The total potato harvest is 13% down on the five-year average of 5.6m tonnes at 4.9m tonnes, according to the annual Agriculture and Horticulture Development Board (AHDB) estimate.

The relatively low production figure is a result of an estimated 4.4% drop in planted area, and a 12% drop in average yield.

The crop was heavily impacted by a combination of late planting and the prolonged hot and dry weather that stalled tuber growth in June and July.

The one area of Great Britain that avoided the effects of the summer heatwave was Scotland. Potatoes grown north of the border enjoyed a 3% increase in yield against last year to 49.2 tonnes per hectare (t/ha).

But the total production of potatoes in Scotland was still down, due to a decrease of 1.6Kha in planted area.

Average yields in England were 40.1t/ha, a 20% decrease from the 49.9t/ha seen last season.

Sector Strategy Director at AHDB Potatoes, Dr Rob Clayton, says the average yield decrease is the result of large variations from field to field.

“Growers were battling a shortage of water this year, the combined June and July period was one of the driest on record. Fields that were irrigated will have enjoyed a reasonable crop, while in others yields were very low.”

Only 53% of the land in Great Britain planted with potatoes this year had access to irrigation, according to an AHDB estimate.

“We won’t run out of potatoes” continued Dr Clayton “we didn’t in 2012, and we won’t in 2018. But what consumers will notice is a wider range of shapes and sizes in the bag they bring home to cook with.

“These shapes and sizes are a normal part of any harvest, they’ll still taste great and will still contribute to the nation’s vitamin C and fibre intake.

“With fewer potatoes around this year supermarkets won’t be able to only choose from the ‘middle’ section of sizes – hence more variety in the bag.”

UK Potato Processors’ Association Comment

UK processors (crisp and French fry manufacturers) anticipate that the impacts of this year’s weather conditions will continue to be felt by the sector until at least summer 2019, when the early potato crop starts to be lifted.

At the start of the year cold and wet weather conditions, due to the ‘The Beast from the East’, contributed to late planting of crops in many areas. Problems were then compounded by unseasonably high spring and summer temperatures (including 10 consecutive days in July where recorded temperatures rose above 30⁰C) and a complete lack of rainfall in some areas.

Since mid-August weather conditions have improved, with growers making the best of a difficult season. However, these latest figures from AHDB confirm that there will be serious issues in terms of availability and quality of potatoes for processing through the first half of 2019.

As well as lower volumes of crop put into storage, the adverse growing conditions has impacted upon the quality of the potatoes and therefore the amount of useable crop. Potato size, defects and colour are the most notable impacts driven by levels of dry matter, secondary growth, cracking and bruising.

In addition, the combination of in field stress caused by the weather conditions, and the fact that some crops were harvested later than normal (to allow more time for them to grow), is likely to mean an increase in the volume of materials encountering an early dormancy break. This has significant implications for sprouting, which will lead to increased weight loss from stored tubers, increased sugars and will particularly impact on long term storage.

Similar adverse weather conditions were observed across many parts of mainland Europe, and this will limit surplus materials available for import. The lack of a definitive position on potato and potato seed importation, post-EU exit on 29 March 2019 only adds to the challenges faced by the sector.

UK potato processors are working with growers on scheduling to ensure maximum use of the usable crop and the whole of the supply chain is working together to ensure that they can continue to provide high quality finished products.

Processors are limited, to an extent, by the physical characteristics of specific varieties required for crisp and French fry production, but will of course take a pragmatic and flexible approach on specifications wherever possible.

More statistics and analysis from this year’s harvest can be found here.