Store management critical to protect potato profits, warns UAP

Potato growers must exercise extreme caution in terms of managing their stores this year if they are to avoid serious problems and incur significant crop losses, according to United Agri Products (UAP).

"After a promising start, this really is turning into a very difficult season. Although the earlier threat from blight has subsided somewhat, growers certainly can't afford to relax," emphasises UAP potato specialist Barrie Florendine.

"Growing conditions throughout the country have been exceptionally difficult, particularly on farms with heavier soils or fields where drainage is impeded. Crops that are currently in the ground therefore have a considerably higher than normal 'rot potential', which makes it very important to formulate a strategy to maximise recovery. There's very little that's commercially positive about the situation, but careful planning will limit the damage and maximise the tonnage of saleable tubers.

"Much will depend on harvesting conditions and the weather during the early storage period. Clearly there's little that can be done to influence some of the issues that will arise, so it's important to plan for those which you can. There is no magical 'chemical' answer to the difficulties which growers face this year, so it's vital that they work closely with their agronomist to consider all the options. The key is to know what you're lifting and to get tubers dry and cool as quickly as possible. That will require detailed forward planning and knowledge."

Barrie Florendine advises growers to consider the following actions:

• Keep a record of each field showing water-damaged areas. These can then be used by the harvesting team to pinpoint problem areas.

• Identify your best crops, those with long term storage potential. Plan your lifting campaign around them.

• Have a 'fall back strategy' for the worst affected areas. Consider keeping these parts of the crop separate, if practical. Some lots may need dispatching for immediate use. Remember the basic principles of getting the tubers dry and taking field heat out of them.

• Plan to allow a minimum of three weeks from the start of desiccation before lifting can be considered 'safe'. For some crops it may be longer. By this time, spores should have lost viability. In seasons such as this, any skin damage that allows bacterial infection can significantly increase the risk of rotting in store.

• Have a team talk with your lifting crew. Explain the issues clearly.

In terms of storage, remember the following:

• Get crops dry as soon as possible.

• Be prepared to use refrigeration equipment early on if air temperatures are not suitable for cooling.

• Be careful not to overfill boxes.

• Keep bulk stores level and even to aid air flow and take particular care to avoid soil cones.

• Check all your harvesting and storage equipment.

• Plan how you will load your box stores to ensure best air flow patterns.

• Be prepared to sterilise grader equipment, particularly where bacterial rotting is prevalent - you might need to wash down with a Jet 5 solution between fields.

• Monitor and record all aspects of crop activity. Manage accordingly.

"This may sound like a lot of extra aggravation when growers are already busy, but time invested now and at harvest to segregate crops will generate a big payback during storage," comments Barrie Florendine. "The combination of blighted and rotten tubers caused by the wet season, together with warm soil temperatures and humidity, will create numerous potential pitfalls in store this year. A number of growers will need to move potatoes before Christmas, which means that anything that's good enough to keep beyond that time should command very good prices."