Red currants are hardy shrubs that produce tender, tart red berries in late June to mid-July. With their upright growth habit and attractive, maple-like leaves, red currants are a wonderful addition anywhere in your landscape. The plants are self-fertile so you only need one.
|Common name||Red currant|
|Botanical Name||Ribes rubrum|
|Mature Size||4-5 ft. tall, 3-6 ft. wide|
|Sun Exposure||Full sun, partial shade|
|Soil Type||Loamy, well-drained|
|Soil pH||Neutral to acidic (6.2 to 6.5)|
|Hardiness Zones||3-7, USA|
How to Plant Red Currants
Plant bareroot plants from nurseries early in the spring before they leaf out. Prepare the soil according to the requirements below. Cut all canes back to six to ten inches above soil level. Leave three to five feet between plants.
During the first growing season, keep new plants well-watered with one to two inches of water per week if there is not sufficient rainfall.
Red currants fall under the ban of members of the Ribes genus, which is still in effect in Arkansas, Arizona, California. Delaware, Hawaii, Idaho, Massachusetts, Maine, Michigan, North Carolina, New Hampshire, New Jersey, Rhode Island, New Mexico, Washington, and West Virginia. The law from 1911 prohibits nurseries to grow and sell the plants due to the white pine blister rust, a fungus that needs two hosts to spread, and members of the Ribes genus are particularly susceptible. Although most red currants are immune to the disease, they were included in the ban. If you live in a state with the ban, you cannot have the plants shipped to you from a nursery in another state.
Red Currant Care
Established shrubs do not require much maintenance; they are tough and forgiving but be careful not to damage the shallow roots when weeding.
Red currants need full sun at least for half of the day. In warmer climates, they do best with full sun in the morning and partial shade in the afternoon, as intense sunlight can burn the leaves.
The soil needs to have good water-holding capacity and at the same time should be well-drained with good aeration. Silt or clay loam with a high amount of organic matter is ideal. Sandy soil heats up too much in hot weather. To counter this, amend the soil with organic matter and keep it moist with two to three inches of mulch.
The ideal soil pH is 6.5 but red currants can be grown in a wider neutral to acidic pH range.
Established plants only need regular watering up to the point of harvest, after which their active growth stops and they don’t need extra water unless there’s an extended drought. Deep drip irrigation works best for their shallow roots.
Temperature and Humidity
Red currants are winter-hardy, however, their bloom in the early spring makes them susceptible to late frosts. They don’t do well in temperatures above 85 degrees F.
The combination of a warm, humid climate with poor air circulation makes them especially susceptible to powdery mildew.
Red currants are heavy nitrogen feeders. Fertilize the plants in the early spring with one quarter to one third pound complete fertilizer (10-10-10 or 12-12-12) in a circle around each plant. Also give the plants an extra nitrogen boost by scattering composted manure around the plants.
Types of Red Currants
- ‘Red Lake’ is a popular cultivar with large, flavorful, juicy berries. It is susceptible to mildew and does not have good tolerance of late spring frosts.
- ‘Rovada’, the preferred cultivar of commercial growers, is a heavy producer with large berries. While it is highly resistant to powdery mildew, it is prone to cane blight.
Red currants turn red when ripe. The longer the berries remain on the plant, the sweeter and more flavorful the berries (don’t wait too long though, as wildlife love the berries too). Because the skin of the berries is very tender and rips easily, to prevent a juicy mess, don’t harvest individual berries. Instead, cut off the whole berry clusters at once with bypass pruners or scissors.
Red currants produce most berries on two- and three-year-old canes and pruning follows that pattern. The goal is to have about eight fruit-producing canes of different ages on the plant.
Prune during dormancy and always remove all diseased, broken, or misshaped canes. In the first winter after planting, remove all except for six to eight of the strongest canes. In the second year, do the same with the new growth and also remove all but four to five of the strongest shoots from year one. Repeat this in year three. By the end of the third year, you will have three or four canes for each year of the plant. Remove all old canes that do not bear fruit any longer. They are easy to identify by their dark color.
If you remove canes in error, don’t worry, the plant will bounce back with plenty of new shoots the next year.
Propagating Red Currant Plants
You can propagate red currants from an existing healthy plant by tip layering, which will produce the same plant as the parent. Place the tip of a cane in the soil and cover it with an inch of soil, then secure it with a rock or a brick. In a year, sometimes sooner, it will develop roots and you can separate it from the mother plant and transplant it.
Common Pests & Plant Diseases
Red currants are most commonly affected by powdery mildew, currant aphids, and leaf spot, which cause leaf damage and defoliation. Cane blight is a severe fungus that leads to the wilting and death of canes. The best way to prevent powdery mildew is to plant resistant varieties. Proper pruning and spacing between plants also reduces the risk of powdery mildew.
Why are red currants illegal?
Because of the white pine blister rust, they are still banned in certain states (see Warning above for details).
How long do red currant bushes last?
They are long-lived and can bear fruit up to 20 years.
Do red currants have thorns?
No, unlike most gooseberry varieties, they don't have thorns.
“Welcome Back Black Currants: Forbidden Fruit Making a Comeback in New York.” Cornell.edu. N.p., n.d. Web.
McKay, Stephen. Currant and Gooseberry Variety Review. Cornell University College of Agriculture and Life Sciences Cornell Cooperative Extension