Protecting your tomato plants from powdery mildew
There are hundreds of types of powdery mildew. Pictured below is what powdery mildew commonly looks like. It usually starts down low and towards the center of the plant and works it way upwards.
Sulfur dust is an organic way to protect your plants against powdery mildew. If you use sulfur dust — not sulfur powder — on your tomatoes you will not have much of a powdery mildew problem. Read more information about applying sulfur dust here.
If you do not use sulfur dust, you will get powdery mildew it at some time or another. Usually you get your crop of tomatoes before it takes the plant but remember, the leaves are the food factories of the tomato plant. And when diseased, this puts stress on the tomato plant just like a disease would put stress on you. Apply sulfur dust when you first see powdery mildew and it should stop it from spreading to the rest of the leaves.
Powdery mildew is a fungus living on the leaves and it spreads to nearby leaves and plants. Once you have it, use sulfur dust to stop the spread.
The powdery mildew fungus spores/germs are in the air and more easily attach themselves to moisture on the leaves. The sulfur dust prevents the spores from reproducing.
Water in the mornings so that the plant and leaves have all day to dry and the water evaporate. Be careful of sprinklers coming on at night and the overspray/mist from them getting your leaves wet. Some varieties get powdery mildew more than others.
When planting, leave space between plants for better air circulation and keeping plants from touching each other and spreading the mildew. Mildew likes cooler, shady areas…..direct sunlight kills or slows down growth.
Once you notice the powdery mildew, apply sulfur dust to correct and stop the spread and improve some of the above issues.
You are welcome to share this information with others—clubs—perhaps share this with your general membership to include those that could not attend the lecture, family, friends, etc.
Dave Freed “The Tomato Guy”