Lycium

Lycium is a genus of flowering plants in the nightshade family (Solanaceae). It comprises about 70 to 80 species of shrubs or small trees, often with spines, distributed across warm temperate and subtropical regions of the world, including the Americas, Africa, Europe, and Asia.

Leaves are simple and alternately arranged. Flowers are small and tubular with a five-lobed corolla, typically ranging in color from purple to white. They are usually pollinated by bees. The fruit is a berry, about 0.5 to 2 centimeters in diameter, ripening to red, orange, purple, or black depending on the species. Many Lycium species produce edible berries.

The best-known cultivated species are Lycium barbarum (goji berry) and Lycium chinense (Chinese wolfberry), grown for their berries and used in traditional medicine and cuisine. Lycium ruthenicum (black goji) is another species valued for its dark berries. Beyond fruit production, Lycium species are used as ornamentals and hedges due to their dense, thorny growth.

Invasive status: some species have become problematic outside their native ranges, notably Lycium ferocissimum (African boxthorn), which has established dense thickets in parts of Australia and New Zealand, displacing native vegetation and complicating management.

Taxonomy: Lycium belongs to the family Solanaceae, subfamily Solanoideae, and tribe Lycieae. Ecologically, flowers attract bees, and birds disperse the ripe berries. The genus includes both widely cultivated species and wild relatives with ecological and horticultural significance.