Gooseberry flowers are small, usually green with pinkish petals, they open in early spring. They are self-fertile, and don't need another gooseberry plant to produce fruit. They do however need to be pollinated in the normal mode of nature. The actual Gooseberries will grow 1 or 2 per flower with a cluster of tiny seeds at their core. Various varieties of gooseberry produce varying colors of berries, green, gray - green, black, or purple. They can be as big as a plum, or as small as very Big blueberry.
Prune the bush to have a somewhat open center, which promotes good air circulation, access of sunlight and ease of harvest- as the thorns are very bothersome . Some gooseberry bushes are very dense and require pruning to harvest and avoid bloodying your hands on the thorns. Don't over - prune as other problems may be created, such as sunscald.
Starting in the Gooseberry bushes fourth winter, prune out all 4-year-old shoots and leave only five or six of the healthiest, and most upright new shoots that came up from the soil level.
Aphids -Yellowish-pink to pale green plant lice that suck plant juices. They are a soft-bodied, oval/pear shaped insects and are commonly found on nearly all varieties of plants, vegetables, field crops, and fruit trees.
Mites - Spider mites and Gooseberry Mite
Fruit Worms - Multiple varieties
Gooseberry Sawfly is a pest in some areas , and is controllable if caught in time. See - Garden Flies
Scales are sometimes a problem, as they are on all fruits, but are rarely a major problem.
Rusts, such as White Pine blister rust.
Botrytis and Anthracnose will cause rot of leaves and young growth, particularly stems in contact with the soil or those splashed upon by overhead watering
Powdery mildew is by far the most deadly disease of gooseberries, it can destroy a harvest very rapidly. Powdery white patches, will develop on fruit and foliage, and eventually darken. Try to obtain a cultivar that is resistant, such as captivator, green finch, Martlet or Remarka.
Periodic sprayings of baking soda helps control many forms of mildew. I've had success using a mix of Neem oil which is water soluble, and baking soda, a tablespoon of each to a quart of water. The Neem oil serves multiple purposes, primarily insect control and the baking soda helps fight mildew.
You can also fight the spread of mildew by trimming dormant plants to the ground level, and practicing proper garden sanitation. Removal of any and all plant debris. Proper disposal of diseased plant tissue - NOT IN THE COMPOST.
The average yield from a healthy and mature gooseberry bush is about 8 lbs. per bush, a good yield is 10 -12 lbs per bush. Harvesting gooseberries is best done with 2 hands, holding one branch back while carefully picking with the other, so as to avoid the nasty little thorns.
Harvest can usually commence in mid summer. Some people, myself included, prefer to pick them slightly under-ripe for use in cooking and preserves. You can leave some on the bush to enjoy fresh as well, but don't allow them to rot or scatter around the grounds as this creates more problems later on.