Potato Growing Guide: Mildew

Symptoms and Detection of Mildew

• On the leaves : Appearance of oily brown spots with pale green halos on the upper surface, and white down on the underside of the leaves.
• On stems and petioles : Visible brown spots, leading to drying out and weakening of the stems.
• On plants : Young plants can be quickly destroyed, while adult stems break easily.
• On tubers : Appearance of brown spots on the outside and rusty marbling on the inside, making the tubers unfit for consumption.

Early detection of symptoms is essential to limit damage and prevent the rapid spread of the disease in crops.

Mildew Prevention with Patativerse

Choice of Resistant Varieties

Patativerse offers certified potato plants and late blight-resistant varieties to reduce the risk of infection. Our professional-grade varieties are selected for their resistance to disease.

Crop rotation

Crop rotation is crucial to prevent the fungus from building up in the soil. Patativerse advises against replanting potatoes in the same spot for several years in a row.

Garden Cleaning

Proper garden maintenance, such as removing dead leaves and plant debris in the fall, helps prevent mildew from persisting in the soil. Patativerse recommends combining this technique with sufficient space between plants to promote air circulation.

Adapted Watering

Preferably water the base of the plants in the morning to avoid wetting the foliage, which encourages the development of mildew in the event of excessive humidity.

Use of Plant Manures

As a preventative treatment, apply plant purines such as those based on nettle, comfrey or horsetail, to strengthen the plants' resistance to mildew.

Means of Fighting Mildew

Application of Bordeaux Mixture

Bordeaux mixture , applied at a concentration of 25 g/L every 15 days, is effective in combating mildew. It acts as a protective barrier on the foliage.

Use of Bacillus subtilis

Bacillus subtilis products are a biological treatment that helps control the progression of mildew in an environmentally friendly manner.

Elimination of Affected Parties

Immediately remove and destroy affected leaves and stems to limit the spread of the disease. Patativerse recommends regularly monitoring plants to detect and treat infected areas.

Uprooting Contaminated Plants

In the event of advanced infection, uprooting contaminated plants helps preserve neighboring crops by preventing the spread of the fungus.

Approved Fungicides

In the event of a severe attack, the use of an approved fungicide is recommended, with the help of a technical advisor for optimal and safe use.

Horsetail Decoction for Prevention

Horsetail decoction is a natural method which, when applied regularly, helps prevent mildew and strengthens the plants' defenses.

Additional Information and Recommendations from Patativerse

Downy mildew develops rapidly in conditions of high humidity (>90%) and temperatures between 10°C and 25°C. It is recommended to use the Mileos OAD computer model to plan downy mildew protection strategies based on weather forecasts. In addition, controlling Alternaria is also recommended in conjunction with downy mildew for complete protection.

Patativerse reminds us that for spraying, air injection nozzles allow for better leaf coverage, thus improving the effectiveness of treatments. By applying these good practices and selecting certified quality plants , you will optimize the resistance of your crops to mildew.

Patativerse: Your Supplier for Healthy Potato Growing

With Patativerse, benefit from certified and resistant potato plants to reduce the risk of late blight and crop losses. We offer free quotes , personalized technical advice, and delivery throughout France to ensure a healthy and productive crop. Order your potato plants today and benefit from Patativerse's expertise to optimize the protection of your crops!