Currants are edible berries produced by shrubs of the genus Ribes, native to temperate regions of the Northern Hemisphere. The three commercially significant types are blackcurrants (Ribes nigrum), which are intensely flavored, and the milder red and white currants (Ribes rubrum). White currants are a less-pigmented cultivar of the red variety. Understanding where these fruits thrive requires examining the specific geographies, climates, and unique legal restrictions that have historically limited their cultivation.
Global Geography and Commercial Production
Commercial currant production is overwhelmingly concentrated in Europe, which accounts for the vast majority of the world’s harvest. Blackcurrants are the most economically significant of the Ribes species, with large-scale farming dedicated primarily to juice and processing markets. The three largest global producers by volume are Russia, Poland, and Germany, benefiting from the cool, northern climates necessary for the plants to flourish.
Poland is a dominant force in the global market, often serving as the primary exporter of processed blackcurrant products. Red and white currants are also staples in European agriculture. Redcurrants are produced extensively in countries like Poland, Germany, France, and Hungary, while Germany and the Slovak Republic are noted for their specialized production of white currants. Outside of Europe, commercial production is relatively small, but New Zealand has established itself as an important research and development center due to its suitable temperate climate. North American production in the United States and Canada remains a niche market, partly due to historical cultivation issues.
Essential Climate and Soil Requirements
Currant bushes are native to northern latitudes and are extremely cold-hardy, requiring environmental conditions to produce a viable crop. They thrive in climates characterized by cool, moist summers and sufficiently cold winters, which is necessary to satisfy the plant’s chilling requirement for proper dormancy and fruit set. The dormant plants can withstand temperatures as low as -20°C, making them well-suited for regions with harsh winters.
The ideal soil for currants is a deep, moisture-retentive loam that is also well-drained, though they can tolerate a range of soil types, including clay and silt. A high organic matter content helps retain the necessary moisture, as the plants prefer consistently moist conditions. Currants also favor a soil pH that is slightly acidic to neutral, aligning with the typical conditions found in their native temperate habitats. Currants can tolerate partial shade, a characteristic that historically allowed for their planting beneath taller orchard crops.
The North American Growing Restriction
Currant cultivation in the United States has been complicated due to an ecological threat. The federal government imposed a ban on growing Ribes species in the early 1900s because the plants serve as an alternate host for the fungus Cronartium ribicola, which causes White Pine Blister Rust. This fungal disease is highly destructive to five-needle pine species, and the blackcurrant is the most susceptible host.
The federal prohibition was repealed in 1966, delegating regulatory authority to individual states. Consequently, the legality of growing currants varies widely across the country, with many states maintaining strict regulations, especially in areas with large white pine populations. States like Maine and North Carolina still prohibit or heavily restrict the planting of European blackcurrants (Ribes nigrum). Other states, including Ohio and Michigan, now allow the cultivation of rust-resistant blackcurrant varieties. However, even these resistant varieties face challenges, as the rust has mutated, making previously immune cultivars susceptible again.