Jostaberry is a cross between a gooseberry and a currant that represents an improvement on both. Unlike gooseberry, jostaberry (except for the 'Orus 8' cultivar), happily, has no thorns. Meanwhile, compared to currant, jostaberry bears a much more abundant harvest. The fruits (berries) of this shrub in the Grossulariaceae family occur in clusters and are produced on a deciduous bush that grows to be 3 to 6 feet tall and wide.
If you are trying to identify jostaberry from its fruit, take note that the color of the berries changes as the growing season progresses. When they first appear, they are green. They change to red and to purple before maturing to the color they attain when they are ripe: violet-black. An identifying feature that remains more constant is leaf appearance. A jostaberry leaf is green, has prominent veins, bears teeth along its edges, and is divided into irregular lobes.
Among other features, jostaberry is valued for its fast-growing quality and for its ability to bear fruit in relatively cold climates. Learn how to grow and care for this unusual fruiting shrub.
|Botanical Name||Ribes × nidigrolaria|
|Plant Type||Deciduous fruiting shrub|
|Mature Size||3 - 6 ft. tall and wide|
|Sun Exposure||Full sun to partial shade|
|Soil Type||Loamy to sandy; well-drained; average moisture|
|Soil pH||6.0 to 6.5|
|Flower Color||Purple, red|
|Hardiness Zones||4 to 7 (USDA)|
|Native Area||Hybrid, no native range|
How to Plant Jostaberry Bush
When to Plant
Plant jostaberry in mid-spring. The shrub will still be dormant at this time, which reduces the chance of transplant shock. A mid-spring planting also gives the plant time to become established before the heat and drought of summer arrive.
Selecting a Site
Choose a full sun location with good drainage for your jostaberry bush.
Plant jostaberry bushes 6 feet apart from one another. This gives each bush enough room to reach its maximum size without casting shade on the plant next to it. Adequate spacing also helps cut down on infestations of certain plant diseases and insect pests.
To install the plant in the ground, follow the same rules you would for transplanting any shrub, including the rule that the width of the planting hole should be twice that of the root ball.
Jostaberry bush will yield an optimal harvest if grown in full sun. In the North, it will tolerate partial shade, but will not perform as well. At the southern end of its growing range (zone 7), it will profit from some afternoon shade.
Jostaberry bush prefers a well-drained soil that with lots of decomposed organic matter mixed into it. However, it will tolerate a soil on the sandy side as long as you water well.
This plant requires an average amount of water. However, take into account the soil type where it is growing. Water drains through sandy soil more quickly, requiring more frequent watering.
Temperature and Humidity
One of the strengths of jostaberry is its relative hardiness (to USDA zone 4) for a fruiting bush. It can survive temperatures to as low as -40 degrees F but also holds up well to summer temperatures in the median zones. It does requires a chilling period of 1000 hours in order to produce fruit. This make fruit production a little more sketchy when grown in the heat and humidity of the South (below zone 7).
Fertilize with compost every spring. In addition, use a mulch such as straw which, along with suppressing weeds, helps retain soil moisture and releases nutrients as it decomposes.
Types of Jostaberry
There are different cultivars of jostaberry. Distributors don't always distinguish between them, selling them generically as jostaberry bushes. In some cases, a particular cultivar represents a cosmetic difference rather than a practical improvement. If you can find them, cultivars include:
- 'Josta': the original cultivar and the one most commonly available
- 'Red Josta': fruit has more of a reddish tinge than it does on the original
- 'Jostine': bears larger berries than the original does
- 'Jostaki' (also called 'Jogranda' or 'Jostagranda'): bears even larger berries than 'Jostine'
- 'Orus 8': may represent the most improvement over the original, with superior-tasting fruit and extra resistance to diseases
Jostaberry takes 2 to 3 years to bear fruit. Harvest when berries have turned bluish-black and are firm to the touch. The time of year when this happens varies according to climate. In some areas, you can harvest in July. In others, you need to wait until later in the summer.
Under the right conditions and with the right care, jostaberry bushes will bear fruit for ten to fifteen years. The berries can be frozen after harvesting. Jostaberry is self-pollinating, so you do not have to grow more than one. However, growing multiple plants may increase pollination and result in larger harvests.
Pruning is an important part of jostaberry care. The fruit grows only on canes that are at least one year old. After a few years, canes get old and productivity declines. So each winter, prune out the oldest canes, along with any dead, diseased, or damaged canes. Such pruning keeps the plant vigorous by releasing more energy into generating new canes.
Propagating Jostaberry Bushes
Before propagating a plant, make sure it is legal to do so. When in doubt, acquire new plants through nurseries. Cultivars tend to be patented. For example, the 'Jostaki' cultivar of jostaberry is patented.
If you grow a currant, gooseberry, or jostaberry and wish to have more, it is possible to propagate your plant in either of two ways, and you can undertake both operations in spring: by cuttings or by offshoots. Here’s how:
Take a cutting any time of year except summer which can stress the plant. You need bypass pruners, a container, potting mix, a pencil, a shovel, and rooting hormone. Follow these intructions:
- Inspect the outer part of the shrub. You are looking for the most vibrant growth on the newest branch tips. Cut a segment about 10 inches long using sharp pruners. Make your cut just under a leaf node.
- Fill your selected container with potting mix.
- Using a pencil, poke a hole 5 inches down into this mix, in the center of the container.
- Strip off any leaves from the bottom half of the cutting.
- Dip the bottom half of the cutting in rooting hormone.
- Insert the bottom half of the cutting in the hole, tamping the mix down around it.
- Water well.
- Put the container in a bright location but out of direct sun, and keep it moist while new roots are forming. Using the pencil, check the moisture content of the mix daily; stick the pencil into the mix around the perimeter of the container and bring up enough of the mix to inspect it. The mix should be damp but not soggy. Water whenever it is getting too dry.
- Depending on conditions, it could take several months for the cutting to root. For a cutting taken in early spring, you should be able to transplant it outdoors in late summer or early fall.
You can also propagate via an offshoot, a method that requires just two supplies: pruners and a shovel. Here's how:
- Bend a young, pliable branch down to the ground at the start of the growing season.
- Hold this branch in place with any heavy object available (for example, a stone), placed a bit back from the tip of the branch.
- Cover the tip with soil.
- By the end of the growing season, the tip will have sprouted roots of its own. Using your pruners, separate the resultant "offshoot" from the main plant and transplant it to the selected garden location.
Jostaberry is cold-hardy to zone 4. If you feel that you are in a borderline zone and wish to insulate your bush against freezing temperatures, apply a 3 inch layer of mulch around the base. Avoid piling up mulch against the trunk, which invites diseases and pest damage.
Common Pests and Plant Diseases
Jostaberry bush is relatively resistant to diseases. This is especially true of the cultivar, 'Orus 8.' Your main challenge will be keeping wild birds from eating the berries before you can harves. Cover the shrubs with netting to keep birds and other pests from stealing your harvest.
There are also the usual, smaller pests to be on guard against. Pests that attack the plant's foliage include slugs, snails, and aphids.
What do jostaberries taste like?
The taste is unusual, because it is both sweet and sour. It is sweet like a currant, but even sweeter. There is a hint of sourness, but it is not as sour as a gooseberry. Jostaberries are often used to make jams, jellies, and juices.
What is the origin of the berry's name, "josta?"
"Josta" is formed from parts of two German words, one for blackcurrant (Johannisbeere) and the other for gooseberry (Stachelbeere).