In the last visit to the site, I noticed that one of my gooseberry bushes was sick: some of the berries darkened, and some of them were covered with a velvety whitish coating. Aroused, and immediately began to look for the cause of such a deplorable state of the plant. As a result of her online research, she gave her pet a disappointing diagnosis – powdery mildew, which is one of the most harmful diseases of this culture.
Powdery mildew is caused by the pathogen under the sonorous name of “fungus sferoteca.” First of all, it affects precisely the gooseberry berries – first, a white powdery coating (mycelium) appears on them, which is easily peeled off. Subsequently, it hardens, acquires a brown hue, and becomes covered by a network of black dots – the fruiting bodies of the fungus in the wintering stage. At this point, the berries often begin to crack and fall. The disease also spreads to leaves and branches and in severe cases can lead to the complete death of the bush.
The main method of controlling American powdery mildew on gooseberries is to plant resistant or slightly affected varieties of this crop: Golden Light, Date, Komsomolsky, Russian, Northern Grape, Muscat, and many non-bearing varieties, also usually not very susceptible to this disease.
Do not ignore banal prevention. To do this, all suspicious and frankly diseased shoots must be removed from the bushes in early spring or late autumn, without showing excessive enthusiasm. The fact is that total rejuvenation can provoke an accelerated growth of young branches, which are most affected by powdery mildew. It is also recommended to systematically pluck and destroy loose berries and leaves, dig the soil around the bushes annually, feed the plants with potash and phosphorus fertilizers, thin out the plantings (to improve their ventilation), and uncompromisingly destroy all weeds under the bushes.
Of course, chemical preparations are the most merciless to American powdery mildew, but they must be able to choose, giving preference to the least toxic species, and also used strictly in accordance with the manufacturer’s instructions. The safest for your health and environmental conditions on your site should be considered closed kidney treatment in early spring or after full harvesting of berries.
With a moderate and weak infectious background, a good effect can be achieved by regularly spraying the affected gooseberry bushes with the following relatively harmless solutions:
- 50 grams of soda ash and 50 grams of laundry soap per 10 liters of water;
- 10 grams of copper sulfate and 200 grams of soap per 10 liters of water;
- 1 part mullein to 3 parts water, insist 3-5 days (depending on weather conditions), dilute three times, strain;
- 3.5 kilograms of greenfield sow thistle per 10 liters insist 8-10 hours, strain.
The treatment with the above drugs is best done after completion of the flowering of gooseberries and to fix it, repeat it another 2-3 times with a frequency of a week and a half.
This fall, I plan to use the full range of preventive measures against powdery mildew in order to prevent this infection from spreading to the still healthy gooseberry bushes. Fortunately, the affected plant is located at some distance from the main plantings. And in the spring I plan to plant small garlic along a row of gooseberries and currants – they say that its characteristic “aroma” repels many garden pests, and the phytoncides released are deadly for harmful microorganisms and pathogens.