I recently bought new African violets. They all looked good until I noticed white powder on the leaves of one of my miniature ones. It may not be apparent at first, but if this isn’t treated, it will kill your plant. What is the powder on your African violet leaves? Powdery mildew.
It is hard to see
It isn’t noticeable until you get up close.
What is powdery mildew
It is a plant pathogen called an obligate parasite meaning it can only grow and reproduce on a living plant. It infects green tissue, including leaves, stems, and flower parts. The powdery mildew has small root-like haustoria that obtain their food from the African violet cells in the epidermal layer.
(Merriam-Webster: Haustoria: a nutrient-absorbing outgrowth of a fungus or parasitic plant that penetrates the tissues of the host organism)
It’s all pretty gross isn’t it? The poor plant. You can see the it on the flower stem below, as well as on the leaves.
How to get rid of powdery mildew
The good news? It is easily controlled if caught early and there are many ways to treat it. Some people use Lysol to spray their plants. Spray carefully as the aerosol can damage plant parts. I have not done this but would recommend a light hand with the spray if that is what you decide to do.
I HAVE used Neem oil. It worked for me and it worked overnight. I have not sprayed this plant yet as I just discovered the problem. I will show you pictures later after I spray it. Any type of fungicide that is labeled for use on houseplants will work. The key is to catch it early before it damages your plant.
Notice below it is on the back of the leaves as well as the front. When you spray the plant, make sure you spray the back sides of the leaves, as well.
Why do our plants get Powdery Mildew?
It seems like it happens a lot in the winter when we warm our houses up during the day and cool them down at night. That paired with stagnant air, sets the plant up for an attack. Air circulation is a big factor. I find I don’t often get it on the plants where there is a ceiling fan running all the time.
This plant was under grow lights in the kitchen where there is little air circulation and humidity is high.
At this time of year, check your plants often and you will catch the problem early before it damages the plant.
Have a great week, plant friends!