23 October 1998

Late liftings put the emphasis on potato quality…

By Andrew Blake

POTATO lifting is well behind schedule and fears are growing for the unharvested crop. But promising prices mean growers must focus on quality, stress specialists.

Only 55% of the UK crop was out of the ground by last weekend, according to the British Potato Council. Last year 81% had been lifted by the same time.

Anglian Produces Simon Bowen reckons 61% of the firms crops had been cleared compared with 72% last year and 75% in 1995. With frost hitting some areas and soils waterlogged, harvested crops need monitoring extra carefully, he advises.

"There is uneasiness about what is going into store. Drying and proper curing is absolutely paramount." Skin setting is slow and there are more misshapen tubers prone to mechanical damage than normal, he notes.

Choosing correct post-harvest tactics is a balancing act best achieved crop by crop, says ADAS national potato specialist Dennis Buckley. "You need high humidity for curing and low humidity for drying. If there is a lot of wet soil on the tubers drying is first priority." Ventilation air should be below 90% relative humidity to do much good. "But it is generally OK to blow if it isnt pouring with rain outside."

Once tubers are dry, good skin cure to prevent disease entry and further moisture loss should be achieved by holding crops at 12C (54F) for 10-14 days, he explains. Late liftings which are potentially suitable for supermarket outlets could justify the extra £4.50/t for a fungicide treatment, he adds. "Growers should consider using Fungazil if the crop looks good."

In Shropshire Beesons Ashley Joule reckons as much as 60% of the firms Saturna for long term storage was still in the field earlier this week. "Rule number one is dont let lifted tubers get rained on," advises Mr Joule. "Keep sheets with trailers to deal with sudden downpours."

Wet weather has brought unexpectedly high levels of star cracking, and powdery scab is the worst for a decade, notes Branston Potatoes Lincs-based field director David Nelson.

With some growers finished but others only half done, this years potentially more valuable crop could justify paying contractors or neighbours to help speed operations, suggests Mr Nelson. "Growers must make every effort to get work rates up." Lifting directly into boxes for curing now before grading later could pay.

worthwhile.

Potato harvest

* Latest for five years.

* Quality fears increasing.

* Only half done in places.

* Store care crucial.

FEW growers can be blamed for finding themselves with unharvested crops, believes fenland-based MBM agronomist Tim Berry. "Most people are pulling out all the stops and stretching gangs as far as humanly possible." Burn-off decisions were especially hard to make this season because of poor crop size or low dry matters, he explains. "It was a question of do you safeguard what you have and risk having it out of spec or do you leave it to grow on." With missed markets potentially cutting returns by £50/t most growers took the latter option, he believes.

POTATO LIFTING

&#8226 Latest for five years.

&#8226 Quality fears increasing.

&#8226 Only half done in places.

&#8226 Store care crucial.

Tricky harvest

Few growers can be blamed for finding themselves with unharvested crops, believes fenland-based MBM agronomist Tim Berry. "Most people are pulling out all the stops and stretching gangs as far as humanly possible." Burn-off decisions were especially hard to make this season because of poor crop size or low dry matters, he explains. "It was a question of do you safeguard what you have and risk having it out of spec or do you leave it to grow on." With missed markets potentially cutting returns by £50/t most growers took the latter option, he believes.