Progress made in terms of the potato harvest 2023 remains very slow, according to Teagasc.

Crops specialist, Shay Phelan said that the continuing poor weather conditions show no sign of improvement.

Currently, there are estimates that approximately 20-30% of the national main crop remains to be harvested.

“However, this varies from region to region, with the south and east suffering the worst effects of the recent storms,” Phelan said.

“It’s a similar situation in the UK and in the Netherlands; they also estimate that 25-30% of the crop has yet to be harvested.”

Many soils are waterlogged and so trafficability is poor and makes harvesting very slow. In most cases, harvesters are travelling at between 1-2km/hour, so naturally it will take longer to complete the harvest.

Rot in potato harvest

There have also been many reports of soft and pink rots in crops, especially where the water table was high.

“Waterlogged areas should be avoided at all costs, as these will slow down the process and only bring more trouble into the store,” Phelan continued.

“They also pose a serious risk of damaging expensive equipment.”

Potato growers are being strongly advised to store high risk areas, e.g., tramlines and wet headlands, in separate boxes and leave them near a door where they can be accessed quickly if needed.

“As temperatures drop during the rest of the season, crops will become more difficult to dry and cure so again this process will take time,” he added.

“Gangrene also becomes more of a problem in colder wetter conditions, so try to reduce physical damage as much as possible. This involves constant monitoring of the entire harvesting process.”

When taking samples to test for damage, growers should make sure to take them from different steps along the process including the lifting shares, from the different webs on the harvester, and from different depths within the boxes.

This will give a clearer insight to where damage is occurring during harvest which can then be addressed. This will need to be completed daily and especially when moving from one crop to another.

Northern Ireland

Meanwhile, in Northern Ireland, College of Agriculture, Food and Rural Enterprise (CAFRE) advisor, Leigh McLean, is confirming that the record rainfall in October has exacerbated problems already created for potato growers, as a result of the wet summer. 

“While there is little growers can do but wait until ground conditions improve, there are some points to consider while they wait,” McLean explained.

“Firstly, while the water is still evident in the fields, growers should mark out the waterlogged areas.

“When harvesting recommences, the extent of these areas will be clear and these potatoes, if possible, should be kept separate from those harvested from drier areas. 

“Attention should also be kept on already harvested stocks.” 

According to the CAFRE representative, there have been few good conditions for harvesting potatoes this year and there are already many reports of soft rots in potatoes already in store. 

“Growers are advised not to try to grade out rotting potatoes as this will only spread infection through the rest of the stock,” McClean added.

“Instead ventilate at-risk potatoes, ideally with positive ventilation systems, to dry and mummify the rotting potatoes.” 

Growers are being specifically advised to take samples of potatoes from all stocks of potatoes in-store.

These should then be placed in a hot box (25°C for three or more days under high humidity). 

This will speed the expression of any potential infections or damage and allow growers to assess the potential for long-term storage or to prioritise risky stocks for quicker marketing.