This herbaceous plant comes from the Solanaceae family; the overground part of the plant looks like a tuft with one or more stems of varying height that are enlarged at the nodes and green in colour, sometimes with shades of purple. The tubers are different depending on the cultivar and vary in their oval and elongated oval shape, and size. The colour of the peel can be yellow or reddish in the yellow varieties, while the white varieties have yellow peel.