Potatoes are nature’s perfect energy storage capsules: ideally designed to withstand a period of dormancy and then burst into life as the next growing season approaches. For thousands of years, humans have benefitted from tubers’ unique dormancy adaptation. In the last 50 years, we’ve figured out how to benefit even more by expanding on nature’s design: now we produce tubers by the thousands of hundredweight; then manage them in storage for months longer than nature originally intended. Still, nature ultimately calls the shots. To achieve what we need from our potato crops, we need to work with potatoes’ natural physiological stages.
The physiological age of your potato crop starts right at planting, based on the health of the seed piece you put in the ground. Any stress to the seed or subsequent plant — be it moisture conditions, nutrient levels, weed, disease or pest issues, among others — will translate to more stressed, physiologically “older” tubers at harvest.
This year, there was far too much rain in some regions and far too little in others. To make matters worse, harvest conditions varied from over-warm to wet to freezing and snowy. The challenging growing and harvesting conditions mean farmers likely harvested physiologically older, harder to store potatoes this fall.
Though it’s never a good idea to load your harvest into your storage building, close the doors, and go on vacation, this year’s stored crop is likely to need extra careful attention. Every farmer should be very, very actively monitoring their piles throughout the entire storage season for soft spots and sprouting.
While CIPC can stress tubers when applied too early, 1,4 DMN can help settle a pile when it first enters storage. DMN is a biochemical (a synthetically produced, but naturally occurring chemical in potato tubers) that inhibits sprouting, decreases tuber water loss, and is scientifically proven to have fungistatic qualities.
There are several effective rescue products should tubers start to push out of dormancy earlier than desired. 1,4 Zap, available for the past four years in the United States, is newly registered for use in Canada as of this past August. The product has had strong uptake amongst U.S. producers, who appreciate its 95 – 100 per cent efficacy and ease of use.
No matter how effective the rescue product, it can be very difficult to hold potatoes back once they hit a certain physiological stage. Therefore, staying on top of sprout suppression will be extremely important this year.