Did you know there are determinate and indeterminate potatoes?! If you’re a keen gardener, you have probably heard about tomatoes being determinate or indeterminate, but surprise – potatoes are too!
What does determinate mean?
Determinate refers to the fact that these plants will reach a certain ‘determined’ height or size, and produce a limited number of fruits or vegetables before dying off. In the context of potatoes, determinate potato varieties produce a single layer of potatoes just below the soil surface. Their leafy growth is more bushy and wide than tall. They generally produce fewer potatoes than indeterminate varieties, and they tend to be earlier in the season after around 70 to 90 days.
Plant determinate seed potatoes about 10 cm deep. There is no need to mound up soil at their base, but mulching is still a good idea ensuring that the potatoes are not exposed to the sun. Plants will stop producing new growth once potatoes are established and flowering commences, then the plants die off.
What does indeterminate mean?
Indeterminate means that these plants do not have a certain ‘determined’ height, size or production. As long as these plants are kept healthy, and have their needs met, they will continue to grow bigger and produce more. Plants continue to produce new growth indefinitely until frost or winter arrives.
In the context of potatoes, indeterminate plants are capable of producing potatoes at multiple levels up the stem, so, although you plant them at the same depth as determinate potatoes (10 cm), you will want to keep mounding them up as they grow. Often these varieties have a longer growing season, and are a mid to late harvest.
Mounding up the stem of the plant with soil, mulch, chopped leaves or straw as the season progresses helps to support their tall, often floppy stems. It also means more potatoes will form in the increasingly high mounds, to a maximum of up to about 30 cm above the original level. That makes indeterminate potatoes the best kind for planting in the “potato tower” or “potato bag” style planters.
What potato varieties have you had the most success with? Throw your answer in the comments section below!
Determinate Potato Varieties
The early season varieties tend to be determinate potatoes, such as Rocket, Swift and Cliff Kidney.