As you know my collection is not large. So far, I've only had an issue with one plant that I'm aware of. It was Epicattleya Tropical Jewel 'Hihimanu'. The plant was half Epi. stamfordianum and the leaves were a bit more tender than most of my other plants. I'm not absolutely sure it was the Physan that caused the problem though. Could have also been all the misting I was doing at that time. (I don't mist foliage any more, it was a brief foray) The plant did have problems from the beginning, hence the Physan. If I ever decided to try these newfangled biological products, I'd give the Physan use up, at least in any plant pots. Guessing it's not a good combo.