The recent heat wave sweeping through Canada’s Ontario province has put a damper on the potato harvest, according to Dr. Eugenia Banks, a renowned potato specialist at the Ontario Potato Board. In her latest email newsletter, Dr. Banks highlighted the challenges faced by farmers due to the soaring temperatures.
By noon, the mercury is touching a scorching 29C, making it perilous to dig up potatoes. Ideally, potatoes should be harvested when the pulp temperatures are between 10-15C. Any temperature above 18C can lead to diseases like soft rot and Pythium leak, which can infect the tubers through any bruises or minor wounds.
Importance of detailed records

at P & K Vander Zaag Farms.
Credit Dr. Eugenia Banks
Dr. Banks emphasized the importance of monitoring pulp temperatures to ensure the health of the crop. P & K Vander Zaag Farms, one of the prominent farms in the region, has been meticulous in recording details such as pulp temperature, variety of the potato, date, time, truck number, and storage name.
Such detailed records can be invaluable in case any issues arise later in the storage piles.
Mark VanOostrum, another expert in the field, revealed that approximately 70% of the processing crop has already been harvested. Despite the challenges, field frying is on track, which is seen as an effective method to sidestep potential storage issues.
On the fresh market front, Shawn Brenn estimates that the harvest is about 70-90% complete, with variations depending on specific areas within the province.
Summer growers have wrapped up their harvest, a sentiment echoed by Kevin Brubacher, who is in agreement with Brenn’s assessment.
Quality at retail outlets excellent
Dr. Banks, ever the potato enthusiast, shared her personal observations, noting, “I’ve been checking potatoes at grocery stores, and the quality I’ve seen is truly excellent.”
However, the weather remains unpredictable. The latest forecast hints at a cooler climate accompanied by four potential days of rain. Dr. Banks mused, “How does one plan in such conditions? Mother Nature continues her unpredictable antics. But then again, what else is new?”
Source: Dr. Eugenia Banks, Ontario Potato Board
EugeniaBanks@onpotato.ca
Cover photo: Jessica Vander Zaag of P & K Vander Zaag Farms showing pulp temperature records. Credit Dr. Eugenia Banks