Imported currant worm

This is the most serious insect pest of currants and gooseberries, with the latter being the favored host. Foliage is consumed by several small, spotted, caterpillar-like larvae. The adults are sawflies about the size of a house fly. There are two generations per year, with damage occurring in spring and again in late summer. Malathion and rotenone will control this insect. Start looking for damage shortly after the leaves have fully expanded. Usually the second generation is less severe than...

Fertilizer

If the site was prepared properly and phosphorus and potassium were added based on the soil test, no additional phosphorus or potassium fertilizer should be required. Currants, gooseberries, and elderberries will benefit from applications of nitrogen. Young plants should receive 1 to 2 tablespoons of a high nitrogen fertilizer like ammonium sulfate, ammonium nitrate, or urea annually in the spring. Older plants should receive 3 to 4 tablespoons of high nitrogen fertilizer in the spring....

Gooseberries

Fruit is large, purplish red, and sweet. The canes are moderately vigorous, but are very spiny. For trial. Poorman. Hardy and moderately productive. Red fruit is the largest of any American type. Somewhat less thorny than most cultivars. Pixwell. Hardy and moderately productive. Medium-sized fruit is pink and mild flavored when mature.

Planting and spacing

Gooseberry Plant Spacing

In Wisconsin, spring planting is preferred for gooseberries, currants, and elderberries. Set dormant plants as soon as they are received from the nursery, or transplant them directly from the propagation bed. Before planting, remove damaged or broken roots or stems and cut back the top portions to 8 to 10 inches, depending on the size of the root system. Plant with the lowest branch at or just below the soil line. Water thoroughly after planting to settle the soil around the roots, and water...

Elder shoot borer

The larval stage of this insect is a worm that bores in the stems and shoots. The adult moth lays eggs in July and August in canes at least 1 year old. Eggs hatch the following April or May. The larvae feed first within the unfolding leaf whorls, then bore into new lateral shoots. When partially grown, they migrate to the ground shoots, entering these at the bases and feeding upwards into the shoots. When the larvae are fully grown in mid-June, they leave the ground shoots and tunnel into dead...

Powdery mildew

Powdery mildew is a common fungal disease that is generally more serious on gooseberry than on currant. The fungus overwinters in pruned or broken twigs. In the spring spores are released and infect leaves and shoots. Signs of the fungus white patches on the surface of leaves, shoots, and berries first appear in May or June on lower parts of the bush. The patches enlarge, merge, and develop white, powdery masses of spores which can start new infections. Eventually the fungus turns reddish-brown...

Anthracnose

Anthracnose is a common leaf spot disease of both currant and gooseberry. The anthracnose fungus overwinters in leaf and twig debris. One type of spore ascospore is ejected from debris and carried by air currents to newly emerging tissue. A second type of spore conidium is splashed by rain to new tissue. Because fungal spores come from the ground, the first infections of the year are often on lower parts of the bush. Early season infections produce spores that cause additional infections. Thus,...

San Jose scale

These insects are small, grayish disk-shaped specks about 2 mm across with a raised spot in the center. They are most frequently found on the canes. For most of its life, the scale insect is incapable of movement, and merely sits and sucks out the plant juices. Heavily infested plants will have canes encrusted with scales. In such cases, single canes or even entire plants will be killed. Dormant sprays of lime sulfur or superior oil will control San Jose scale.