How to Use Baking Soda for Treatment of Powdery Mildew on Lemon Trees

Lemon trees are susceptible to powdery mildew because they grow in warm weather, the same climate that powdery mildew fungi favor. Baking soda is a nontoxic way of tackling the problem. The chemical compound doesn't kill fungus. Instead, it makes the environment too alkaline for fungi to survive. That's why a baking soda spray works against powdery mildew and black spot, two fungal diseases. In particular, a blend of baking soda and horticultural oil used as a foliar spray effectively treats powdery mildew, according to research done at Cornell University.

Things You'll Need

• 4 tsp. baking soda
• 1 gallon water
• 1 oz. horticultural oil
• Sprayer

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Instructions

1. • 1

     Measure 4 tsp. of baking soda, 1 gallon of water and 1 oz. of horticultural oil.

   • 2

     Add the baking soda, water and horticultural oil to a spray tank. Agitate the blend to mix it.

   • 3

     Spray the foliage on one section of the lemon tree to provide full coverage. Wait two days and examine the leaves for signs of damage from the spray. If there's none, prepare a fresh solution and spray the rest of the tree, completely covering its leaves.