Using ProMix for C. rex seedlings

[Abe1997]

Hello everyone!

Does anyone have experience growing seedlings in promix? I know HR uses this almost exclusively. I live in Redlands Florida, south west of Miami. HR has similar conditions to ours in monsoon season.

I have about 10 flasks of various rex and Triumphans eager to come out this season. Planning on experimenting with mounting a few, some in inert with charcoal, others in small grade orchiata and a few of the moyomba varieties in sphagnum.

Also just an observation from some dowiana seedlings I deflasked last fall, I grew half in typical light for seedlings I.e. bright indirect light, low direct, and the other half in direct Florida winter and spring sun. The results were insane the plants that I kept in traditional conditions used here in the state are growing steadily but are still very small. The ones left in the sun are already forming 3 plus growths and firm thick wide leaves wider than an inch. They are almost purple in color at this point.

Of course this is such a small sample size, only about 75 seedlings in each group, of a single species from a single parentage. I will not keep them out like this as summer approaches, but I took this idea from a couple of brazilian friends who grow their seedlings mounted in the brightest highest parts of their orquidario with great results. Just some food for thought!

---------- Post added at 12:43 PM ---------- Previous post was at 12:16 PM ----------

They have since been moved to the same flats but here are a couple side by side for comparison.

[isurus79]

Interesting questions!

First, I want to confirm that HR is H&R Nurseries in Hawaii? If so, I'd like to point out that their climate is very different than yours! I used to live in Honolulu and can tell you that the rainy season is March/April and that summer is very dry with no monsoons.

Is this the promix you're talking about? PRO-MIX Orchid Mix

If so, that should work fine. I've used similar mixes on my Cattleya seedlings.

However, I have to say, it sounds like your dowiana experiment gave you a great clue regarding how best to grow your rex seedlings. I'd focus on that approach and see if you can improve on it somehow.

[Abe1997]

Thank you for the info! The summers aren’t as rainy where I live in comparison to the rest of south Florida thankfully, although the humidity is insane.

I didn’t realize there was another ProMix haha! The ProMix I meant was

PRO-MIX HP BIOFUNGICIDE + MYCORRHIZAE

It is mostly peat moss (65-75) and perlite.

[isurus79]

Originally Posted by Abe1997

Thank you for the info! The summers aren’t as rainy where I live in comparison to the rest of south Florida thankfully, although the humidity is insane.

I didn’t realize there was another ProMix haha! The ProMix I meant was

PRO-MIX HP BIOFUNGICIDE + MYCORRHIZAE

It is mostly peat moss (65-75) and perlite.

I was wondering about that! I'd probably only use peat for Cattleya seedlings in a very controlled greenhouse or in Arizona (i.e. dry place). Definitely not in Florida!

[Ray]

There are LOTS of different ProMix variations.

As to using that one, many years ago, Harvey Brenneise and Rob Halgren (Littlefrog, of some forums) of Michigan State, at the time, published an AOS article about using such “mud mixes” for orchids.

They can work, it you had better be very careful with watering.

Neither one uses it any longer.

[Fairorchids]

I got some Vanda compots from Carmela a few years ago. I put them in the greenhouse upon receipt, but did not look at them closely.

When I was ready to break them up some 2-3 months later, all the roots were dead. They were potted in something that looked like ProMix (not sure which formulation), but under my watering schedule, it did not work at all.

For de-flasking Cattleyas, I always use:

50% chopped spaghnum
25% seedling size bark
12.5% seedling size charcoal
12.5% Perlite (not coarse)

[thefish1337]

I watched a talk by Roy and he says they use Pro-Mix Biofungicide.