Botanical Gardens - Orchid lover's dream

[jmmehler]

This year, the Birmingham Botanical Gardens has been renovating their exhibition greenhouses. All their plants have been relocated to the working greenhouses. Currently, they do not have any staff with orchid expertise, so they asked our Alabama Orchid Society for some volunteers.

I stopped by there this morning for an initial inspection. Rather than go at it with just my own ideas, I’d like to solicit some advice on some very specific topics.

Water conditionsThey use city water, which seems to have a very high mineral content. Most of the orchids are covered in white residue. On the one hand, I realize this is not good. On the other hand, the overly rotted medium that the orchids are in, probably create enough acidity to counter the high PH in the residue left by the water.

Greenhouse ConditionThe ‘growers’ Greenhouse is in good condition. Phals, paphs, & Phrags are in a section under shade cloth. They will soon remove that cloth, as the winter will bring less light. They have working heaters and ventilation. Humidity level is very good. Only select staff waters the orchids, and they will be getting some training, which will include the fact that recently transplanted orchids should require more water than those in rotted media.

PlantsThere are several dozen phalaenopsis in desperate need of repotting. Would appreciate comments on;
• Choice of bark mix, or moss.
• Was thinking of a diluted vinegar solution to wipe down the leaves, and then to spray in order to begin to eliminate the mineral residue

There are dozens of cattleyas and dendrobiums in rotted medium, also covered in mineral deposits. I lifted up a gigantic dendrobium whose root system had completely rotted out. While the medium was lava rock, it was so old that the algae, roots, and other debris kept it too moist. I’m tempted to over winter them in empty clay pots. Could use any and all input

There are hundreds of paphs, phrags, and oncidiums all seem very happy, with completely drenched roots and rotted medium. Operating on a large scale, they have mixed their own paphs medium based on a recipe they found, using commercial quantities of bark, expanded rock, and moss. Looks good but they haven’t started using it yet.

There are many Bulbaphilums (or as we say here in the South 'Bubba' philums. The giant ones with the 2 - 3 foot phalaenopsis looking leaves are in hanging baskets and look good even with the mineral residue. The smaller varieties are on tables and don't look so good.

Vandas are hanging in baskets and are unremarkable.

Obviously this is much more work than one person can do on a part time basis, but I figure on coming in a couple of times a week, on my way into work. Weekends may not be available at this time. Would also appreciate any ‘plan of attack’ strategies.

Thanks

[My Green Pets]

It is a dream, I would love to work in a place like that. Been thinking recently that it might be time to move back to the States...

[jmmehler]

It's been an interesting couple of days. I've repotted more than 60 phalaenopsis. The medium had completely deteriorated and shrunk to a point that each pot was only filled about 1/2 way.

It seems that for the summer time, in addition to watering every few days, that their commercial misters come on for 10 seconds at a time, every 10 minutes. All the pots contained very wet medium.

The most interesting point was that most of the plants had the most massive root systems I'd ever seen. About 4 of the Phalaenopsis had to be repotted into 7 inch pots, but only after hacking away significant portions of their roots. On one of these plants, I cut off 4 spent bloom spikes and left one new one. About 45 plants were potted into tall 6 inch pots. On many of the plants, I cut away between 2 and 4 inches of dried out root stock just so that I could fit them into 7 inch pots.

I believe the wet medium initially rotted out the roots, but that the humid conditions allowed new ones to develop. Despite being neglected, and covered in mineral deposits, almost all of the plants seem to be flourishing. It will be interesting to see how much they deteriorate in the fresh bark mix.

Still do not know how to tacke the Cattleyas Bulbaphyllums, and Dendrobiums. The Paphs and Phrags all drenched, and seem happy.

[AnonYMouse]

10 seconds of mist every 10 minutes probably doesn't amount to much water if it is sprayed broadly and not directly.

With that kind of set up, mounting some might be a good idea.

[GardenTheater]

Wow, you got a lot done with those Phals!!!

[My Green Pets]

Would love to see some photos.

[jmmehler]

Some photos First two are before and after on the Phals.

3) Example of outgrowing large slat baskets

4) One of the tables full of Phrags and Paphs

5) Thriving roots (Phael) despite soaking wet conditions

6) Some of the large Cats

7) Blooming Cat and Dend

8) Example of the mineral build-up on all the leaves

9) Bulbophylums (or as we say down south "Bubba" Phylums)

[Troythediver]

How are the plants thriving in these conditions? Do they add chemicals that kill mold and bacteria? The over watered old potting media orchids I have bought definitely did not thrive. Is this a temperature humidity thing?

[Nexogen]

Originally Posted by Troythediver

How are the plants thriving in these conditions? Do they add chemicals that kill mold and bacteria? The over watered old potting media orchids I have bought definitely did not thrive. Is this a temperature humidity thing?

Orchids are far tougher than they look.

[RandomGemini]

One thing I wanted to suggest that someone else on the forum mentioned and I'm sorry I can't remember who it was...

I purchased a phal from Trader Joe's with hard water stains on the leaves. It looked very similar to one of the plants in your photos.

OB to the rescue! MAYONNAISE! No joke! Dab a TEENY bit on a paper towel and rub it over the leaf in a circular motion, then wipe the leaf down with a paper towel dampened with hydrogen peroxide to remove any of the mayo. The leaves look gorgeous now. If you're gonna go to all the work to repot everybody and get them happy, you may as well make them look fabulous too!

Good work you're doing! You must be so proud of all of them!