Help! Q&A

E. from Beaumont emailed in a question:

Q: “Everything seemed to be going well with a new African violet until a couple of days ago, when I noticed that its pot was molding or mildewing or something. It had gray "fur" -- the same look that improperly dried-out shoes might have -- spotted around the pot itself. Another pot, also in a north-facing bay window doesn't have the problem, but it is not planted in the same batch of soil. The pot does not sit in water and the light it gets is filtered through white Roman shades. The air conditioning stays at about 76, rain or shine. What gives – and should I be worried about the plant?”

A: Bottom line? If it’s fuzzy, it’s fungus. So how did it get there when the other plant is doing fine? There are four pieces to this puzzle: clay pot, potting soil, Roman shades and sunlight.
To have fungus, you have to have spores. Since the clay pot was new, it likely came from either the original container you bought the young violet in, or the soil. Both of these are possibilities, since the healthy plant is one you grew and the fuzzy pot contains a plant you bought. Since you didn’t use the same soil in the affected pot as you did in the clean pot, it’s suspect.

Adding to the right conditions for fungus growth are the light conditions (the sick pot is in the same window as the healthy one, but on the side that gets less sun). The heavy filtering from the Roman shade might help your electric bill, but it’s not helping the violet. Also, the clay pot allows water to seep through, adding the moisture the fungus needs to grow.

What to do? Sponge the outside of the pot down with a 10% bleach solution. It should kill the fungus. Place the pot where it will get more light. If after that, you still have a problem, you can try re-potting it in clean soil, but you likely won’t get rid of all the spores. In that case, hard as it is, ditch it and start over. Be sure to toss it in a plastic bag and seal it before tossing it out. Don’t spread the spores in a compost pile. If the pot looks clean but the plant starts looking diseased, toss it.