It’s really a very simple formula: increase the length of the growing season and increase the potential yield and profits from a potato crop. There isn’t much that can be done to avoid a season-ending frost sometime during the fall, so perhaps the most feasible way to extend the season is to plant the crop early, say potato specialists Mike Thornton and Nora Olsen at the University of Idaho.
In an article published in Potato Country magazine, Thornton and Olsen say that with the stocks on hand report indicating tight supplies of potatoes this spring, there may be even more pressure to get into the field early in 2020 in order to take advantage of higher prices for early harvested potatoes.
“These are both good reasons for growers to consider planting early, but when making decisions on when to start planting, growers should be aware that there are also some substantial risks involved,” according to the experts.
“When you plant potatoes you start a race between the disease organisms that are trying to infect the cut surfaces and wounds of the seed piece, and the tuber tissue that is trying to heal those injuries and produce sprouts that will form vigorous plants,” Thornton and Olsen write. “The plant depends on the seed piece for energy and nutrients for quite a while after emergence.”
Research has shown that the longer the seed piece remains intact, the more productive the plant will be.
Ideally, the seed piece should remain sound until the plant has a chance to utilize all the nutrients and energy stored within it. The seed piece provides a large portion of the plant’s nutrient and energy requirements up until they grow to be about 10 to 12 inches tall. At that time, they have enough leaf area and root system to support plant growth.
To minimize seed decay, it is important to plant at temperatures that promote healing of cut surfaces and encourage rapid sprouting and emergence.
There is an old rule of thumb that soil temperatures at seed piece depth should be above 45 degrees Fahrenheit and climbing before starting to plant seed. This temperature threshold is especially important for cut seed because of the large surface area that must undergo wound healing.
Soil temperatures below 45 degrees Fahrenheit prevent wound healing.