Be on the look out for skin spot!
It’s this time of year when skin spot lesions become apparent and if you are storing a susceptible variety, you need to be washing and checking samples - look for the characteristic round ‘pimples’ - from around the store. The disease can affect varieties to differing extents each year but it’s worth checking the likes of Cabaret, Cara, Desiree, King Edward, Lady Balfour, Marfona, Maris Piper, Santé and Vale’s Emerald for signs of infection.
If you do discover problems when you have washed some samples, talk directly to your customer and see what options are available to you – this is a far less expensive solution than taking a risk and having a load rejected.
Whilst we’re talking about this disease, keep a look out for it on seed stocks too, as skin spot can cause blindness reducing stem numbers and providing a ready source of infection for the daughter crop. The use of seed treatments, such as imazalil/TBZ (Storite Super), can help to control the problem.
Ventilation in cold weather
Following the very cold snap in November/December, temperatures have been much more seasonal of late, even bordering on quite mild conditions in the last week or two. However, be on your guard for the return of the cold and be prepared to take action. The extent of the cold spell last year highlighted widespread problems such as icing up of louvres and condensation on cold surfaces even where insulation levels were significant. These caught a few people out resulting in some unwanted chilling, so be vigilant!
It’s worthwhile checking that you have a back up frost thermostat wired independently of the main control system which can turn the fan off in the event of a problem such as a jammed louvre – it could save your crop.
Also be aware that the use of propane burners in stores can also have some unwanted consequences. Burning fossil fuels releases carbon dioxide and, often, small amounts of ethylene which can trigger an adverse rise in sugars in the crop, darkening fry colour. If you need to use heat remember to keep the potatoes regularly supplied with oxygen providing external conditions permit you to flush.
The benefit of roof space heating to help control condensation has again been evident this year. This keeps the air above the crop at a similar temperature to the potatoes and lowers humidity in the roof space to reduce the risk of moist store air condensing on the cooler building structure.
Senescent sweetening in processing crop
Some of the shorter term processing varieties, like Lady Rosetta and Pentland Dell, will soon be approaching the end of their storage life. Start monitoring fry quality more regularly to detect any deterioration and ensure crops reach their intended market.
Energy & sprout suppression on the agenda for our storage forum
Finally, a reminder that Thursday 3 March is the date for our winter storage forum at Sutton Bridge. Half of the day will be devoted to energy management, the other half to sprout suppression. If you have yet to register, contact firstname.lastname@example.org