Blackcurrant can damage both unopened and open flowers when the temperature falls below . The flowers at the base of the strig are more protected by the foliage and are less likely to be damaged. In midsummer the strigs of green fruit ripen to edible berries, very dark purple in colour, almost black, with glossy skins and persistent calyxes at the apex, each containing many seeds. An established bush can produce about 4.5 kilograms (10 pounds) of fruit each year. Plants from Northern Asia are sometimes distinguished as a separate variety, "Ribes nigrum" var. "sibiricum", of which "Ribes cyathiforme" is considered
Solanum nigrum Solanum nigrum Solanum nigrum (European black nightshade) is a species in the genus "Solanum", native to Eurasia and introduced in the Americas, Australasia, and South Africa. It is also known as black nightshade. Parts of this plant can be toxic to livestock and humans. Nonetheless, ripe berries and cooked leaves of edible strains are used as food in some locales, and plant parts are used as a traditional medicine. A tendency exists in literature to incorrectly refer to many of the other "black nightshade" species as ""Solanum nigrum"". "Solanum nigrum" has been recorded from deposits of the Paleolithic and Mesolithic