Hello and advice needed for Catasetum

[Vermonter]

Hello all. I am very happy to have found what looks to be a great resource. May I dive right in with a question?

It is time for me to repot my Catasetum (Ctsm. atratum ‘Polar Cap’ x Ctsm. tenebrasum ‘St. Frances’). I am considering a mix of medium size fir bark mix with sphagnum and a bit of potting soil. Does this sound reasonable?

Also, I have the newly started bulb and 5 backbulbs. I would like to try starting some of these backbulbs. What is recommended for best results in starting Ctsm. backbulbs?

Many thanks.

[Frdemetr]

Vermonter,
Catasetum is a genus with certain specific demands, and it do not grows well if cultivated like cattleyas or phals.
Catasetums are strictly epiphytic orchids (ie, forget about soil) and demand (at least in brazilian weather): high atmosferic humidity (if not, spider mites will attack), low humidity in the top of the media (coconut chips mixed with carcoal in small pieces are adequate, they don't like tree-fern fiber nor sphagnum), and hight humidity in the bottom of the media. In my conditions, the best way to grow is a kind of 's/h with media', using a plastic pot with no holes in bottom, only in the side, +/- 5cm above bottom line, and filled half with clay material pieces (roofing tile pieces, clay pellets etc.) and half with media. They need to be repoted (almost) every year, and the older roots must be cutted off during repoting. Do not try to divide the plant unless it does by itself spontaneously, the back bulbs will shrink to feed the newer ones.
See that pic I posted before (AOSP Orchid Show, march/2007) to see this method and good luck!

[Vermonter]

Many thanks for the advice, Frederico. It seems that I was headed in the wrong direction with my mix. I will follow your suggestion and use plastic with holes on side, clay pot shards in the bottom. I am embarrassed to admit that I have had this Catasetum 4+ years and have not repotted it before. Nonetheless, it has put out new growth and flowers annually. Now I will get it on schedule for annual repotting.

Best to you.

[smartie2000]

Welcome to the Orchid Board! Sorry I can't help because I haven't grown these guys yet, but maybe soon!

[Frdemetr]

You are wellcome, Vermonter! Keep in mind these Catasetum growing method is adjusted to my weather conditions, maybe you need to implement some modifications to fits your weather! My contribuition is only a suggestion, not a guideline!

[justatypn]

Aboard, its great that you found your way to the OB where our members will help you in your growing enviroment as well as you sharing in your experiences. Glad your here

[Dorothy]

to the best resource of orchid information and orchid loving people on the net!

Here's to OB

[Tindomul]

Welcome to the Board!! Glad you found us, and as you can see, help is speedy around these parts.

[Djarum Black]

Hi Vermonter!

Welcome to the OB! Glad you could join one of the super best fourms on the web! Be sure to post pictures and ask even more questions! Thats how we all learn!
I'm sure I will be talking to you soon!

[CATLOVER]

Hi Vermonter.
I have started to grow my ctsm. semi-hydroponically. This year my Tenebrosum has 6 buds just about ready to open. If you switch to semi hydroponic don't repot until you are ready to start watering again after their waterless rest, when the roots are one half inch or so long.
I use 80% prime agra pellets, 10%charcoal 10% diatomite and soak the medium overnight before repotting. I fertilize with MSU fertilizer. and water once a week.
I hope this was of some help