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
Allium nigrum to 60 cm long and 2.5 cm across. Later the leaves become reflexed. Scapes are smooth and round in cross-section, 80–100 cm tall. The scape carries a dense umbellate inflorescence with star-like flowers up to 9 mm across; tepals white with a green midevein; anthers purple or yellow. The ovaries are black-green (but flushed with red in the Levant) in anthesis, but green when younger or following anthesis. Type species of Subgenus (Section) "Melanocrommyum". Molecular evidence suggests that "A. nigrum" is a polymorphous species consisting of several infraspecific groups. Alliances: Allium nigrum alliance: "Allium nigrum" L. and "A. multibulbosum" Jacq.