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Although many
people today are unfamiliar with these fruits, New Yorkers grew 2,700
acres of them in the 1920s.
Legalities of Growing
In the early 1900s, the federal and state
governments outlawed the growing of currants and gooseberries to prevent
the spread white pine blister rust (Cronartium ribicola). This
fungal disease attacks both Ribes and white pines, which must live
in close proximity for the blister rust fungus to complete its life cycle.
Black currants (Ribes nigrum) and white pines (Pinus strobus)
are extremely susceptible, and red currants and gooseberries exhibit varying
degrees of susceptibility.
Although the federal ban was rescinded in 1966, some northern states still prohibit the planting or cultivation of black currants. In 2003 though, New York State passed a law that modified its ban to allow commercial growers and home gardeners to legally grow red currants, gooseberries and immune or resistant cultivars of black currants throughout New York State.
Some black currant types, such
as the cultivars 'Consort', 'Crusader', and 'Titania' are hybrids that
are resistant to the blister rust fungus. They can be planted in areas
where other currants and gooseberries are permitted.
Choosing cultivars
Ribes are a very diverse genus with hundreds
of different varieties that differ in plant size and form, and fruit flavor,
shape, texture, color and hairiness. While most are hardy to Zone 3 or
Zone 4, a few are hardy to Zone 2. Several types of interest to home gardeners
include:
Red currants (Ribes rubrum, R. sativum and R.
petraeum): Fruits range in color from dark red to pink, yellow,
white and beige, and they continue to sweeten on the bush even after they
appear to be in full color. Many people consider 'Rovada' to be the best
red currant cultivar. Plants are dependable, vigorous, late ripening,
and very productive, bearing long-stemmed clusters of large red berries
that are easy to pick.
White currants: A type of red currant,
white currant cultivars are sold less frequently by nurseries. 'Blanka'
is most commonly available. Berries are large and mild in flavor with
a pale yellow color. Most people prefer 'White Imperial' or 'Primus' if
they are available.
Black currants (Ribes nigrum):
Black currants cultivars such as 'Consort', 'Crusader', and 'Titania' -- which are immune or resistant to white pine blister rust -- are now legal to grow in New York.
Gooseberries: There are two types of gooseberry plants -- American (Ribes
hirtellum) and European (Ribes uva-crispa).
Cultivars of the American type are smaller but more resistant to mildew.
They tend to be healthier and more productive. American cultivars include:
The fruits of the European cultivars are larger and
better flavored. They include:
- 'Invicta' - Considered by some to be the best gooseberry
available in North America. Resistant to mildew, but susceptible to
leaf spot. Very large fruit with bland flavor.
- 'Leveller' and 'Careless' - The standards for British
fruit production. Yellow- and green-fruited respectively.
- 'Early Sulfur' - Yellow, hairy fruit with good
flavor, but susceptible to mildew.
- 'Catherina' - Large green fruit.
- 'Achilles' - Large red fruit.
See also Ribes cultivar review.
Sources of gooseberry and currant plants can
be found at https://blogs.cornell.edu/berrynurseries/.
Site Selection and Soil Preparation
Unlike most other fruit crops, currants and gooseberries tolerate
partial shade and prefer a cool, moist growing area. Northern slopes
with protection from direct sun are ideal. Planting along the side of
a building or shady arbor is suitable as well.
Avoid sites with poor air circulation, which increases
the incidence of powdery mildew. Sloping ground alleviates this condition.
Also avoid light-textured, sandy soils. Rich, well drained soils that
have a high moisture holding capacity are best. Incorporate organic
matter (compost, peat, or manure) to improve the soil, particularly
if it is somewhat sandy. The ideal soil pH is about 6.5.
Planting
Purchase strong, well-rooted plants from a reliable nursery, selecting
either one- or two-year-old vigorous stock. Because currants and gooseberries
begin growth very early in the spring, you should plant them in the
early fall or very early in spring, before the plants begin to grow.
Before planting, remove damaged roots and head back
the tops to 6 to 10 inches. Do not allow the root systems to dry out.
Set plants as soon as possible in properly prepared soil, slightly deeper
than they grew in the nursery. Firm the soil around the roots. Space
plants according to the vigor of the cultivar, keeping in mind that
plants are more vigorous on very fertile soil. As a general rule, plants
should be spaced 3 to 5 feet apart in the row with 8 to 10 feet between
rows.
Trellising gooseberries increases air circulation (decreasing
disease problems), makes fruit easier to harvest, and allows you to
grow more plants in less space. Gooseberries are easily propagated through
tip layering or stool bedding (mound layering).
Fertilizing
Currant and gooseberry plants are heavy nitrogen
feeders. To give the plants a healthy start, work manure into the soil
before planting. Annual top-dressings of composted manure are beneficial
as well. If plants are not vigorous, lightly broadcast about .25 to
.5 pound of 10-10-10 per plant. Avoid fertilizers containing muriate
of potash (potassium chloride).
Mulching
Mulch keeps the soil cool in the summer, retains moisture, and controls
weeds. Spread 2 to 3 inches of mulch around plants and replenish it
yearly. Suitable mulches include straw, lawn rakings, composted manure,
compost, wood chips, or similar materials. Grass clippings make excellent
mulch. If you use fresh straw or sawdust, you may need to apply nitrogen
fertilizer because these high-carbon mulches tie up nitrogen while they
decompose.
Harvest
Remove any flowers so that plants don't develop fruit during their
first season of growth. Expect a light crop the second year and a full
crop by the third. Currants and gooseberries ripen over a two-week period
in June. Berries do not drop immediately upon ripening, so they usually
can be harvested in one or two pickings. Currants can be picked in clusters,
and gooseberries are picked as individual fruits. Expect mature plants
to yield about 90 to 150 pounds per 100 feet of row. Wait for fruit
to turn color before picking. Gooseberries come off easily when they
are ripe. Currants require some trial and error to determine the right
time.
Pruning
Prune currants and gooseberries when the
plants are dormant in late winter or early spring. Remove any branches
that lie along the ground as well as branches that are diseased or broken.
Ribes species produce fruit at the base of one year old wood. Fruiting
is strongest on spurs of two and three year old wood.
After the first year of growth, remove all but six to
eight of the most vigorous shoots. At the end of the second growing
season, leave the 4 or 5 best one-year-old shoots and up to 3 or 4 two-year-old
canes. At the end of the third year, prune so that approximately 3 or
4 canes of each age class should remain. By the fourth year, the oldest
set of canes should be removed and the new canes allowed to grow. This
system of renewal ensures that the plants remain productive because
young canes always replace those that are removed. A strong, healthy,
mature plant should have about eight bearing canes, with younger canes
eventually replacing the oldest.
Diseases and pests
Visit http://www.fruit.cornell.edu/berrytool/
for assistance in diagnosing problems with currants and gooseberries.
Currant aphids, leaf spot and powdery mildew are the most common problems
that plague currant and gooseberry plantings. All disfigure or damage
leaves, and can cause defoliation.
Currant aphids - These tiny, soft-bodied insects feed under young
leaves toward the shoot tips, causing affected leaves to curl downward,
blister, and become reddish. In severe cases, leaves become excessively
distorted and fall off and the fruit does not ripen properly. Insecticidal
soap and certain horticultural oils (check labels) can help control
aphids.
Powdery mildew - This fungal disease is a problem particularly on
European gooseberries. In early summer, a whitish, powdery growth appears
on the surface of leaves, shoots, and branch tips. If left unchecked,
the fungus can progress to the berries themselves. Later in summer,
the growth may turn from white to brown. Warm, humid conditions with
poor air circulation favor powdery mildew. Prune and dispose of infected
branch and shoot tips in early spring. Some homeowners are experimenting
with trellising gooseberries because it improves disease management
and harvestability. Certain horticultural oils (check labels) applied
at first sign of mildew can prevent spread.
Anthracnose and leaf spot - These disease can both become
serious problems, especially in wet, humid years. Symptoms range from
brown spots and yellowing on leaves, young shoots, and stems to early
defoliation. Destroy -affected leaves, and apply mulch -after leaf drop.
San Jose Scale - These insects occasionally infest currant and gooseberry
plants. They feed by sucking valuable plant juices, and in severe cases
they affect the fruit as well. Scale insects are easily seen on the
dormant wood. Prune out and destroy infested canes before new growth
begins in the spring. Certain horticultural oils (check labels) can
help reduce infestations.
Currant borers - These moth larvae burrow in the pith of currant
and gooseberry canes. Infested canes do not die in the fall, but put
out sickly growth in the spring. The adult, a clear-winged moth, appears
in June and lays eggs in leaf axils. To prevent the next genera-tion
of moths from emerging, remove and destroy infested canes before June
1. Proper pruning to remove old canes is the best control.
Currant stem girdler - This immature sawfly eats around, or
girdles, the tips of new shoots, which eventually die and fall off.
Cut off affected tips in May or June about 3 to 4 inches below the girdle,
or if left until later in the season, about 8 inches below the girdle.
Imported currantworm and other sawflies. As soon as leaves expand in
spring, adults deposit eggs on the undersides of leaves along the major
veins. A week to ten days later, tiny larvae emerge and begin eating
holes in the leaves. If numerous, they can strip a bush of its foliage
in a few days. Remove leaves harboring eggs by hand.
Gooseberry fruitworm - This greenish caterpillar feeds in
fruit causing it to color prematurely and fall off. The adult moth lays
eggs on the fruit, and the larvae enter the developing berries and feed
on the pulp, moving from one fruit to another. Several berries may be
tied together by a silken webbing. Handpick infested berries before
larvae move to adjacent ones.
© Copyright, Department of Horticulture, Cornell University.
Website design and coding: Rachel Kennedy and Craig Cramer cdc25@cornell.edu
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