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
Epicoccum nigrum sensitive to essential oils from plants such as lavender and rosemary. This is important in terms of the preservation of artifacts in humid climates, where fungal growth is an important determinant in the deterioration of stone structures and wood frames. "Epicoccum nigrum" produces the glycoprotein allergen Epi p 1 which binds to IgE, sometimes cross-reacting with other fungal allergens. Cross-reactivity was found to exist with "Alternaria alternata", "Curvularia lunata", "Cladosporium herbarum", and "Penicillium citrinum". "Epicoccum nigrum" is associated with respiratory fungal allergies, including allergic asthma, rhinitis, hypersensitivity pneumonitis, and allergic fungal sinusitis. Two pediatric cases of hypersensitivity pneumonitis caused by