The white bumps are actually called lenticels. Lenticels are special pores in the plant tissue that allow oxygen exchange with the outside world, allowing the potatoes to “breathe.” The large amount of moisture we have been receiving caused the lenticels to swell and therefore become visible.

Are knobby potatoes safe to eat?

The plants are wonderful and loaded with buds for 3 weeks now. I dug some last week and had large 4-5 inch around potatoes, but each potato has numerous small bulb potatoes all over each one. They look clean and healthy for eating.

Why are potatoes scabby?

Potato scab is caused by the bacterium Streptomyces scabies. This bacterium is related to certain bacteria that produce antibiotics used to treat human diseases. S. scabies occurs naturally in many soils, from soils with high organic matter content, to coarse and gravelly soils that tend to dry quickly.