Cucumber blight – what is it and why is it so dangerous?
Cucumber blight is the most common disease. It appears both on professional plantations and in small beds in gardens and allotments. It is caused by fungi from the powdery mildew family. Depending on the type of fungi, this disease may alternatively be called powdery mildew or downy mildew. Cucumber blight is a serious condition in which the entire crop is directly threatened. It is manifested primarily by changes in the leaves. In the case of powdery mildew, a white coating appears on the outer side of the leaves. Downy mildew causes olive coating to appear on the leaves and purple spore pockets on the underside.
Cucumber blight is a disease that affects the quality and intensity of crops. Infected plants often stop bearing fruit and cucumbers stop ripening. Those fruits that can be grown are not suitable for consumption. It is worth remembering that weather conditions favor the development of fungal diseases. Warm air and moisture provide ideal conditions for fungi to multiply.
Spraying is effective in the fight against cucumber blight. Professional gardeners most often recommend sprays based on copper and zinc. However, it is worth knowing that this type of spraying is used in the phase of greatest threat, rather than earlier than the end of the inflorescence development phase.
Mix these 2 ingredients together and spray on the cucumbers. Home spraying for cucumber blight
against plant diseases can be excellent care treatments or a complement to professional activities. For cucumber blight, a combination of baking soda and milk is most often recommended. I tested this method myself and my cucumbers are free from fungal diseases. Baking soda is a well-known and natural fungicide. It strengthens the immunity of plants and prevents spore attacks. Milk, in turn, improves the soil structure and provides cucumbers with calcium. The use of milk- and baking soda-based sprays helps to strengthen the condition of plants and protect against attacks of diseases and pests.
Comprehensive prevention is essential. How to prevent the plague?
Before you spray, remember that the key to healthy crops is proper prevention. Many cultivation mistakes made unconsciously create ideal conditions for the development of fungal diseases. First of all, ensure proper air circulation – do not plant cucumbers too densely. When watering, direct the stream of water directly onto the soil, avoiding wetting the leaves, as moisture on their surface promotes infections. Regularly remove the lower leaves and those on which the first disturbing spots appear.
It is also extremely important crop rotation. Pathogens that cause late blight can survive the winter in the soil, so cucumbers should not be grown in the same place more often than every 4 years. Also avoid planting them after other cucurbit vegetables, such as zucchini or pumpkin. Already at the stage of purchasing seeds, you can minimize the risk by choosing varieties with increased resistance to downy mildew. This will give your plants a better start and a natural protective barrier.
How does cucumber blight spread and overwinter?
Understanding the life cycle of pathogens allows you to protect crops more effectively. The spores of the fungi responsible for the plague are carried by the wind, often over very long distances. Infection occurs in conditions of high air humidity and moderate temperatures, especially when there are large differences between day and night. Raindrops, fog or dew on the leaves create the perfect environment for spores to germinate and penetrate the plant. The incubation process of the disease usually takes 6 to 7 days.
Unfortunately, these pathogens are very durable and can survive the winter in the remains of infected plants and in the soil. This is why it is so important to thoroughly clean the beds after the season and avoid planting cucumbers in the same place year after year. Spores left in the ground become a source of infection for new seedlings in the next season, as soon as favorable weather conditions appear.
When home spraying is not enough: professional protection measures
In case of severe infection or in commercial crops where the risk of losses is high, natural methods may prove insufficient. Then it may be necessary to use professional plant protection products, i.e. fungicides. There are preparations available on the market with contact action (for preventive use) and deep or systemic action, which penetrate the plant tissue and fight the disease from the inside. The most frequently recommended active substances include: chlorothalonil, propamocarb or copper preparations. Remember to always use them according to the manufacturer’s recommendations and observe the withdrawal period.
Biological protection agents are an interesting alternative to chemicals. They contain non-pathogenic fungi that parasitize on pathogenic fungi, limiting their development. An example of such a preparation is Polyverse WPcontaining fungus Pythium oligandrum. This is an environmentally safe solution that not only protects plants, but also stimulates them to grow better. Protective treatments, both chemical and biological, should be performed alternately to avoid pathogens becoming resistant.
