Bark=Rot in Catts?

[Sandy4453]

I'm a little surprised, although not really. Yesterday, I spent all day repotting all of my Catts. (and alliances) into LECA, (Hydroton w/charcoal). They were in a standard bark mix (w/charcoal, perlite added). While some were growing new roots and others had pretty good root systems all over, every single plant had lots of root rot. I never overwatered! I fertilized and fed regularly. I thought I was doing everything right???

Every single nursery I've been to here in Fla., have all their Catts. in LECA. I know though there are a lot of growers that use bark for growing Catts. What I don't know is the secret hobbyists have in how the prevent rot with Catts in bark? Mine were in the right sized plastic pots (not oversized) and well ventilated. I'm now thinking of once again transferring them into the netted, plastic pots for better aeration? Do you think this will make a difference or should I leave them as is?

I'd love to know what everyone is using for their Catts. Anyone using bark and what are you doing that I didn't? Or what aren't you doing that I did?

Would love to know what you're all using!

[tuvoc]

As long as you have new root growth and some healthy roots, you are doing OK. The dead or rotted roots are from old growths that will die off naturally as the plant grows. This will happen no matter what medium you grow them in.

Kim

[Lagoon]

Agreed with Kim.

There will always be some root rot as the older growth does die off and new strong growths take their places.
The question is though ... when you say root rot, what is rotting -- old growth, newer growth?

Catts can take alot more moisture then ppl think, but they also need air around the roots, tightly pack media is death to any roots on any orchid.

I grow my catts in sphag and coarse rok. All potted in clay.They do better this way then when I had them in a bark mixture, that dries out faster. Go figure!

[Sandy4453]

tuvoc and lagoon, thanks for your replies. Yes, I know older ps.bulbs will have rot on their roots. I wish I could say that was the only area where I found them yesterday but not so. I've always been leary about the bark though and especially because I do pot my 'chids tightly.

lagoon, what ratio do you use for the sphag. with coarse rok? (is this like sponge rock?). Sounds interesting.

Anybody using the netted, plastic pots?

[isurus79]

I use bark with plastic pots. I cut four wide'ish slits down the sides of the pots and I put wine corks on the bottom of my pots instead of styrofoam peanuts for added ventilation and a few inches of bark on top of that. My pots are REALLY tightly packed, I grow my orchids outside here in Hawaii (which is less hot and humid than southern FLA) and have only had one incident with Catt root rot, and that was because I had inadvertently bought a skinneri that was already infected. This style of potting requires more water during the summer (at least once a day for me), but also allows for weeks of rain to roll through with no ill effects for my 'chids.

[Ross]

Originally Posted by SRF

tuvoc and lagoon, thanks for your replies. Yes, I know older ps.bulbs will have rot on their roots. I wish I could say that was the only area where I found them yesterday but not so. I've always been leary about the bark though and especially because I do pot my 'chids tightly.

lagoon, what ratio do you use for the sphag. with coarse rok? (is this like sponge rock?). Sounds interesting.

Anybody using the netted, plastic pots?

I use waterlily "pots" which have very fine holes/slots so I can use fine bark when I choose. I tend to use coarse bark for most plants, but fine bark/sphagnum mix for the thin roots plants. Everybody gets potted loosely. Don't know what coarse rok is, but lots of alternatives available in US.

[Lagoon]

Coarse rok is just simply - large perlite. I use #3 with chopped up sphag. I've never really measured the amount, more like eyed as I go. I'm guessing about 25% mix in.

[Tindomul]

Normally I grow my catt types in Leca Semi/Hydro. But lately I have been using normal orchid mix. You know, bark charcoal mix. On one large Blc. I used that mix and mixed it with some loose leca for added aeration and a few chunks of sphag for added humidity. I water once a week and mist the top of the pot and plant and any aerial roots 4-7 times a week. That particular Blc. is doing well growing lots of new roots. The other two in bark mix are potted in cone pots. Those square pots with a cone in the center for better air movement. They get dry very quickly and as a result those two plants look dry.

[Oscarman]

As they need repotting, I am moving to S/H for my Catts, using PrimeAgra, Hydroton, etc.

[Bolero]

I don't believe bark=rot. It worked well for most of mine but I have to say CHC is now working even better.

The best Catt growers in Australia though use Sphagnum and the roots have to be seen to be believed.