Answer: Mildew can affect many plants, including tomatoes. The best controls are to enhance air circulation as well as possible by spacing them to allow for air flow, pruning them to increase air circulation within the plants, avoiding overhead watering, and avoiding working on the plants when they are wet. Some gardeners have reported success using a homemade baking soda/oil spray: mix 1 tsp. baking
soda and 2.5 tsp. summer oil (a lightweight horticultural oil)
in 1 gallon of water.Spray this once per week, covering
both upper and lower leaf surfaces. A commercial
alternative is Soap Shield Fungicidal Soap from Gardens
Alive (5100 Schenely Pl., Lawrenceburg IN 47025; ph#
812/537-8650). As with any spray, test on a few leaves and see if there are any adverse effects before spraying the entire plant.
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