Without any organic matter in it I'd be hesitant.

The only plants I have seen in that gritty mix used is Bonsai trees.

Thanks to both of you for your input.

I've followed several of Al Tapla's threads, several hundred pages of information. I'd love to hear from him on this but can't seem to locate him, has anyone seen any recent posts by him? He seems to have started with Bonsai but now recommends his gritty mix for almost anything!

I have about 200 bromeliads, almost all epiphytic, no terrestrial species, but still consider myself to be a newbie.

Gonzer, I've seen a few of your posts and you really seem to know what you're doing! I'm wondering why ephipytes would need organic matter in their pots? I have a dozen or so bromeliads that I've mounted on trees, of course no organic matter there, and they seem to be doing well.

Like I said I have a lot of bromeliads but I admit I don't have very much experience at all. Here's my latest project, 50 Neo Maria; topped with an Alcantarea odorata; surrounded by 8 Vriesea ospinae gruberi. I hope to put it in the house for 2 months over the holidays, hence my interest in changing the pots to gritty mix.

I sure can't embellish upon Nev's answer because it just about sums it up. I will add though that while organics are a must-have in you mix it doesn't necessarily have to be a large percentage. I myself use a (roughly) 20% potting mix, 30% small pumice, and the rest small orchid bark. This can vary by about 10-15% either way depending on what's being worked on.

Thanks Gonzer, I just stumbled onto an old thread where Al Tapla does mention bromeliads. Here's a link to it

Beginner Gardening: Turface on bromeliads? - Dave's Garden

"Al" suggests using foilage-pro 9-3-6 in a weak concentration, weekly to provide nutrients. He's all over Garden web, with rather old posts, but very "scientific sounding" advice. I've successfully used his gritty mix on quite a few potted plants but not yet, with bromeliads.

Onto another question: this neo hybrid, Mariam has very bright color in the center leaves. The outer fringe of leaves are starting to turn brown. I don't have the "bromeliad tree" in very bright light and I'm wondering if the "browning" is caused by that or just natural as the outer leaves age?

Growing broms in trees does contain organic material from the bark, dead leaves and insects just a rainforest.

hotdiggity: not sure how insects, dead leaves, and bark could make their way into roots? Of course if you're talking about the bromeliad "well" collecting those things then yes, of course, they're using organic material. But they're getting that material form the well not from the roots so the composition of the potting mix would be irrelevant, which is the question at hand.

Then how do they thrive in a rainforest?

Hi again, I'm not being disagreeable. I don't think we're talking about the same point. My original question revolved around using gritty mix as opposed to any organic mix in my potting mix. My point is that almost all bromeliads are epiphytes. Defined as: An epiphyte is a plant that grows harmlessly upon another plant
(such as a tree) and derives its moisture and nutrients from the air,
rain, and sometimes from debris accumulating around it. My point is that epiphytes do not need soil for nutrition and are perfectly happy without soil, as in the rain forest attached to trees. The roots of epiphytes can obtain nutrition from the air, as in orchids, but often are primarily used for attachment, as with many if not most bromeliads.

I had a bromeliad for a month in its original store pot and it died. The soil was very organic. I got another one and repotted it immediately in the gritty mix and sprinkled a few plant food on top of the soil. I'm almost certain I did not put gypsum in the mix (I always do but for that one I forgot). I watered it every 3 days over a couple months this winter, both watering the soil and also watering a little inside the leaves which can gather water pockets by design. Last week three "bromeliad pups" started growing around the trunk so it seems the vigor of the plant high. I will be separating these "pups" once they are big and end up with four bromeliads, etc.. Because they are epiphytes(don't bother other plants when in contact with them), I will probably put those pups growing with other plants as arrangements.

Sorry about resurrecting this old thread but I though this experience was worth sharing for those who have gritty mix and bromeliads in mind...