Silverleaf nightshade, a deep-rooted broadleaf perennial, is common throughout California to 3900 feet (1200 m) except in the North Coast, Klamath Ranges, and Great Basin. It is particularly widespread in California's desert valleys, especially in poorly managed fields. Sometime silverleaf nightshade is troublesome in agricultural areas, particularly tomatoes and cotton fields. Large infestations can reduce crop yield and pasture production by competing for soil water and nutrients with desired plants. Once established, it is difficult to eradicate and reduced tillage favors it. Often more problematic are its relatives, black nightshade, S. nigrum, and hairy nightshade, S. sarrachoides, and horsenettle, S. carolinense. Leaves and berries contain varying amounts of glycoalkaloid compounds that can be toxic to humans and livestock when consumed. However, berries are eaten by many bird species and small mammals.
Habitat
Orchards, vineyards, crop fields, rangeland, pastures, forest openings, roadsides, and disturbed, unmanaged places.
Seedling
Cotyledons (seed leaves) are gray-green, narrowly lance shaped and up to 2/5 of an inch (10 mm) long. The first true leaves have wavy edges and are covered with small star-shaped hairs, which require 20X magnification to observe.
Mature Plant
The mature plant is 1 to 3 feet (30–90 cm) tall and has many branches and an open form. Leaves are egg shaped to lance shaped, reach 6 inches (15 cm) long, usually have wavy to coarsely lobed edges, are alternate to one another along the stem, and are covered with dense, short, star-shaped hairs (visible with 20X magnification). The dense covering of hairs give the leaves a dull, silvery green to pale yellowish-green color. Stems often have prickles which range from tan to reddish. Creeping stems produce young shoots that are a dusky, silver-gray and resemble seedlings but do not have cotyledons.
Flowers
Flowers bloom from May through September. They are showy, 4/5 to 1-1/5 inches (20–30 mm) in diameter and have deep violet to light blue (sometimes white) fused petals with yellow centers. Flowers cluster along branches of the flowering stem and the oldest flower grows singly at the tip of the main stem.
Fruits
Mature berries are 1/3 to 3/5 of an inch (8–15 mm) in diameter, globe shaped, and greenish yellow to brownish orange.
Seeds
Seeds are tiny, less than 1/6 of an inch (4 mm) in diameter, semi-glossy, and yellowish brown to dark yellow brown.
Reproduction
Reproduces by seed and creeping roots that give rise to bud shoots.
Related or Similar Plants
- Black nightshade, Solanum nigrum
- Hairy nightshade, Solanum physalifolium
- Horsenettle, Solanum carolinense
