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Gardening in Washington State

Avoiding Strangely Shaped Knobby Potatoes

While growing potatoes is relatively easy, maintaining an even soil moisture is crucial to producing a good crop of well-shaped potatoes. After the plants emerge, potatoes need about 2 inches of water per week, depending on the weather and the type of soil. Regular irrigation will be needed if natural precipitation is not adequate. Wide fluctuations in soil moisture will cause uneven tuber development leading to potatoes with knobby growth, pointed ends, or a dumbbell shape, depending on when the water-stress occurs.


This material is excerpted from the WSU publication Growing Potatoes in Home Gardens FS118E

Submitted by: Marianne Ophardt, July 6, 2015


One comment on “Avoiding Strangely Shaped Knobby Potatoes”

  1. Dirty Harry said on July 8, 2015:

    100 agree.

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