The red potato plant, scientifically known as Solanum tuberosum, is a domesticated member of the nightshade family (Solanaceae). While the edible tubers develop beneath the soil, the above-ground appearance offers distinct visual markers for identification. Understanding the vegetative structure, reproductive cycle, and subtle variations of the foliage and flowers helps guide recognition throughout the growing season.
Identifying Features of the Foliage and Stems
The stems grow upright and are typically green, though some varieties may exhibit subtle reddish or purplish pigmentation, especially near the base or nodes. These stems are sturdy and often have an angular or square cross-section, sometimes appearing “winged” with fine hairs covering the surface. The overall growth habit is bushy, reaching a mature height that usually ranges between one and three feet.
The leaves emerge from the stems in an alternate pattern and are classified as pinnately compound, divided into multiple smaller leaflets. Each leaf consists of several pairs of oval leaflets, usually numbering between six and eight, arranged along a central stalk. The foliage is generally a dark, rich green color and can possess a slightly dull or fuzzy texture due to sparse hairs. This abundance of fern-like foliage creates a dense canopy that maximizes light absorption.
The Flowering Stage and Potato Fruit
Later in the season, the red potato plant enters its reproductive stage by producing flowers. These flowers grow in small clusters called cymes, appearing at the tips of the stems. Each blossom is star-shaped, formed by five fused petals, and features a distinctive set of bright yellow stamens at the center.
For red potato varieties, the flower color commonly falls within a range of white, pink, lavender, or purple. After successful pollination, a small fruit may develop, resembling a miniature, round or oblong green tomato. This true fruit, often called a potato berry, contains numerous seeds. These above-ground berries are toxic due to high concentrations of the alkaloid solanine and must not be consumed.
Visual Differences from Other Potato Varieties
Distinguishing a red potato plant from other potato types often relies on subtle variations in the reproductive and vegetative structures. While all potato plants share the same basic compound leaf structure, the intensity of flower color is a primary distinguishing trait. Many red potato cultivars, such as ‘Red Pontiac,’ produce pink or darker purple flowers, whereas varieties like Russet Burbank are more likely to have white or very sparse blossoms.
The presence of pigmentation in the stem can also be a clue, as red-skinned potatoes may display a more noticeable purplish tint compared to yellow or white varieties. A darker pink or red flower often correlates with the presence of red pigment in the underlying tuber. However, factors such as foliage density and overall growth habit are less reliable for specific identification, as these traits vary significantly even within the red potato category.