NYCorchidman I know it is supposed to be good for orchids as vendors always have it at the shows. I will just use it on my houseplants now. I have only used it a couple of times. Thanks!
SuperThrive, K-L-N, and others contain synthetic root-stimulating hormones. They are intended to be added to fertilizers (if you're stimulating growth, the plant's going to need building blocks, right?)
A half-teaspoon per gallon, used once a month, will be far more effective as a stimulant, and won't harm your plants. In my opinion, the "drops per gallon at every watering" as recommended on some labels, does nothing to stimulate the plant.
This is a really great thread. I had to add that oyster shell and eggshell take time to work so if your plants are showing a calcium deficiency, you have to use something else in the meantime to give the plant a ready source.