Zygopetalum won't grow roots?

[Miri the Wildmage]

Hi everyone,
I bought a Zygopetalum around March, not sure what cultivar. At the time it had a beautiful root system despite the gross rotten medium it was in, and as it had two new growths forming I decided it would be safe to repot. Shortly after repotting most of the old roots died off, presumably just from the shock of repotting since I hadn't let it get too wet or dry. Fine, whatever. New roots soon. However, fast forward about 4 months and although one of the new growths has kept growing and is now almost as big as the rest of the leaves (the other new growth died, but it was kind of damaged when I got it anyway) it has so far failed to produce any roots, and the old bulbs are getting more wrinkled every day from supporting it. At what point in the growth cycle are zygopetalums supposed to produce new roots, and any ideas why mine hasn't? Thanks!
P. S. I've tried kelp, higher and lower concentrations of fertiliser etc. and the plant is potted in bark and sphagnum

[orchidsarefun]

Not sure what your temperatures are like but imo they do not like high temperatures - say over 75f, for an extended period. This is mine I got rootless 3 months ago. It's in my basement with humidity over 50% and high temp under 70f.

[jcec1]

They usually send out roots early in their growth cycle - they also bloom off immature growths as well.

I can't think why it wouldn't grow new roots -as orchidsarefun mentioned they like to be kept cool - in the UK that usually isn't a problem - I also keep them quite damp - watering twice a week and never allowing to dry out.

[rbarata]

Can you post a photo of the whole plant?

[BellaOrquidea]

Ok, so I’m thinking you’re Zygo isn’t liking the media you provided. I think you made the right call by reppotting when the new growth was forming as new growth develops its own roots and these roots are the plants future root system, one died but no biggie since you have some backup bulbs. As far as I know Zygos are terrestrial orchids and they like a free draining mix that is slightly acidic. So I’m thinking that’s why yours isn’t growing. The sphagnum is probably sofocating the roots as they’re constantly wet.

---------- Post added at 02:01 PM ---------- Previous post was at 01:54 PM ----------

Originally Posted by orchidsarefun

Not sure what your temperatures are like but imo they do not like high temperatures - say over 75f, for an extended period. This is mine I got rootless 3 months ago. It's in my basement with humidity over 50% and high temp under 70f.

When I grow mine in that type of humidity and temp mine starts to root rot. Mine’s an inter generic so maybe that’s why that happens. I have a zygolum Rhein something.

[Miri the Wildmage]

Hi everyone, thanks so much for the advice! I think it could well be the temperature - normally the UK is pretty cool until about now, but we've had a really warm spring and are currently in the middle of a heatwave, so possibly it's just been too hot. @bellaorquidea I wondered about that, but I've been careful not to overwater the sphag and as I said it's mixed in with bark so it shouldn't get too saturated. If anything I'd say it's been on the dry side.

All that said, this morning I saw a new growth on one of the old bulbs and what are either new growths or root tips (too early to tell) on the existing newest growth! So I think I'll leave it alone for the moment, make sure it gets some air circulation in this hot weather, and see how it does! Clearly sods law was waiting for me to make this thread so it could all kick off. Hopefully this is the end of my woes with this orchid but I'll keep you all posted! Attached are pictures of the whole plant and new whatever-they-ares.

[Ray]

No fertilizer until the roots are into the medium so they'll stay moist.

[Miri the Wildmage]

Thanks Ray, I really want them to do well so all advice is appreciated!

[Leafmite]

I would flush the pot very well to get rid of any fertilizer and then just use the kelp mix. Perhaps put a layer of NZ sphagnum moss on top of the bark (this will help to encourage root growth), then stake the orchid on top of the moss. Keep the moss damp. The new roots will grow down into the medium.

Good luck!

[Miri the Wildmage]

Originally Posted by Leafmite

I would flush the pot very well to get rid of any fertilizer and then just use the kelp mix. Perhaps put a layer of NZ sphagnum moss on top of the bark (this will help to encourage root growth), then stake the orchid on top of the moss. Keep the moss damp. The new roots will grow down into the medium.

Good luck!

Currently it is staked lightly so hopefully that'll hold it until the roots grow in - It does currently have a thin layer of sphag on top but I think I'm gonna top it up on one side because right now there's a gap there of half an inch between the root tips and the medium, so they'll have a long way to grow otherwise. Thanks for all the support, everyone!