Greene,
I'm not consistent with either soil mix or fertilizer. I'm somewhat careless in my habits. In my rural area, about the only potting soil available is Miracle Gro. I'm not fond of it and I believe the quality now is inferior to what it was a few years ago. I reuse all potting soil. I dump it back in empty potting soil bags and I usually add stuff to it when I use it - compost, alfalfa pellets, oak leaves, really anything organic I might have at the time and then I may mix that with new potting soil or pine bark or ground up tree limbs (I was given a huge pile when they trimmed the power lines in exchange for allowing them to park the equipment in my field). I don't measure much, just mix up what I have until I get something that seems right for the plant. Lots of perlite or sand or both for succulents. Chunky stuff when I want it drain fast. I may or may not toss in a bit of granular fertilize if I happen to have any on hand. I tend to have a light hand with fertilizer, so when I get around to using it, plants get a weak solution until they give me a clear sign they'd like it stronger. Seems to me different plants respond to fertilizer really differently. Some never seem to need it, a few react negatively, some are picky eaters and some eat heartily. That soluble Miracle Gro stuff is usually what they get. Sometimes I might sprinkle a bit of dry fertilize on something. My whole thing is to adjust something when it seems to be needed.
As for that Kalanchoe, I never got around to re-potting it so I have no idea at all what the soil mix is and because I'm unfamiliar with growing it I haven't given it any fertilize at all. I haven't even watered it regularly. Never more often than once a week. It has grown steadily until the rapid growth spell it's in now set in. In the same spot. All that changed is the natural length of the days and the corresponding location of the sun above and decreasing temperatures of the season. I just can't see any sign of a bud at the top, but the leaves are going to be microscopic if they keep getting smaller.
