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 surfaces hairy or hairless; petiole long with a winged upper portion. The flowers have petals greenish to whitish, recurved when aged and surround prominent bright yellow anthers. The berry is mostly in diam., dull black or purple-black. In India, another strain is found with berries that turn red when ripe. Sometimes "S. nigrum" is confused for the more toxic deadly nightshade, "Atropa belladonna", in a different Solanaceae genus altogether. A comparison of the fruit shows that the black nightshade berries grow in bunches, the deadly nightshade berries grow individually. The "S. nigrum" species is a highly variable taxon with many