I think a little goes a long way, to coin a phrase. Something else to look into, and I don't know the answer to this--we are advised down here that Osmocote should not be used if the temperatures will get very high. The coating disintegrates and releases all the nutrients at once. I would think that might be a problem in a terrarium. But I could well be wrong!

Ooooh. That could be a problem in a terrarium in Arkansas. Thanks, GreenElbows! Betty

I put a little Osmocote around my plants in my terrarium about 1/2 year ago. They seem to be growing better, though that may be because I also now spray their leaves with fertilizer water every couple of months. Very often plants grown in terrariums don't get enough fertilizer. But my place does not get extremely hot as GreenElbows cautioned you about, so I don't know if the comparison will work. Anyway, no problems here.

My problem with terrariums is that they are too easy. I put my really rare, hard-to-grow-out-in-the-open, plants in terrariums and they do beautifully but then I get distracted by my ten zillion other plants and then they either dry up (hard to do in an enclosed environment) or just go through what you all know--the stop growing syndrome.

Actually, if I listened to myself first and gave advice second (or third) I would know just what to do and my terraria (OK terrariums) would all be great. First of all, I would restart terrariums every once in a while--every six months?, every year?, maybe every three years?? Even if I restarted them ever at all, that would be better. Second and more appropos, I would fertilize my terrariums. This is really easy to do, but doesn't require special fertilizer or osmocote. It just requires the handy-dandy "dedicated turkey baster" that all terrariumists should have. You feed every once in while, even though the media is already nicely wet. You definitely DO NOT WAIT for the soil to dry out before feeding. All you do is water in the fertilzed water, get every bit of the media nices doused and then you make a little hold in the mix, down to the bottom of the container so that you see the excess water ponding up. Then just use the baster to remove all the excess water until there is no more ponding. You are left with a nicely moist airy soil mix well dispersed with fertilizer, and without any standing stagnant mess that invites, rot, fungi, algae, and decline. That is how I do it, when I do it (if only I would listen). It really is an easy proposition. Much easier than wading though one of my long posts. Turkey basters cost $2, so there is no excuse for not dedicating one to your plants. The excess fertilized water that you remove can be disposed of in another potted plant. So, nothing is wasted. Just keep the baster away from the kitchen.

QED.
Jon