Greetings UBC, I have read over similar posts regarding mold on the dirt of potted plants. This is the first I have ever experienced such a problem. I do not overwater my plants, some of them are very dry and yet this mold persists. There is a white fuzy mold forming on the top of the potting soil in 70% of my house plants. Some of these plants are new and I thought perhaps I got some bad soil, but more recently, my older houseplants that are well established have been developing this mold. I am puzzeled. Most of what I read states "over watering"... I have removed the mold from the top surface of some of my plants, replacing it with a moisture control potting soil, and the mold came back. I wonder if the mold spore count in the air is up? Could this affect my house plants? Furthermore, all of my plants are potted in draining pots, the soil drains, they have good air circulation and lots of light. I have a great variety of plants affected bt this, pothos, zebrina, christmas catcus, succulents... the only ones holding strong are my avacado and aloe. I live in Michigan, I have considered repotting all of my plants, but am afraid this might further shock my plants due to the dropping tempatures and sunlight lessening. Any Help, suggestions would be greatly appreciated. Thank You Renee
Hi, greentree! I used to raise my houseplants "by guess and by golly," and watered them from the bottom. A crust which I later discovered was mineral salts formed on the top due to this habit. Are you sure what you have is mold? If you water the way I did, maybe . . .?
if you're using dirt from your yard in the containers, that might be part of the problem. houseplants should always have sterile potting material. some mold may still develop if you have some bark chips/bits in the soil mix - they'll decay (even if sterilized) and then the mold can start. keeping the soil too moist will promote mold growth, so, that's one thing that you have control over...also, proper air circulation around the plants - keep them spaced so there is ability for air movement and you can also put in a fan to help increase circulation. and, yes, there may be spores being released and they land on another plant and, when conditions are 'just so', they start growing - and the cycle continues. try to avoid touching the soil with the tip of the watering can and always wash implements between use on different plants. also, when re-using containers, always wash them before planting something else in them. i go all-out with it (want to be absolutely sure that i kill anything nasty) and use almost straight bleach and then rinse really well a few times to remove residue. you'd do just as well with water/bleach mixture that is 10% or 20% bleach.
