- The best time to apply Kumulus DF is after flowering, prior to pod set.
- Innoculum blows in during the second and third weeks of July.
- Spores germinate within 1 or 2 hours and visual symptoms occur between 8 and 10 days.
- Treat when symptoms first appear and repeat applications at 7 to 10 day intervals if conditions favour additional infection.
- As many as three applications may be required in one season.
When to Expect Powdery Mildew
- The disease usually occurs during prolonged periods of warm, dry daytime conditions with cool nights favouring the formation of dew.
- Temperature will also determine if and when infection will occur. Spores will germinate when the temperature is between 15°C and 29°C, but they like it best when the temperature is between 20°C and 24°C.
- Water on the leaf surface is not required for germination or spread of the disease. In fact, excessive moisture inhibits infection by washing spores off the plant and by rupturing spores prior to germination