rootless orchids care

[drosera]

Hello people,
Last month I bought some orchids from Ecuador and they arrived with no viable roots. I have some Cattleya, Odontoglossum and Maxillaria, and I placed them within a plastic minigreenhouse with high RH (70-90 %) and Tº between 17-23ºc, with a low light, to promote their rooting.
The plants are no potted, only inside a basket with a little of Sphagnum on the bottom.I also have a little fan inside the greenhouse. I mist periodically the leafs, with a superthrive solution two-three times a week.
After two months, some of them have produced new roots, but Maxillaria (M. striata i M. sanderiana), Odontoglossum (Odontoglossum gloriosum and O. Hallii) and some Cattleya (Cattleya iricolor, Cattleya quadricolor...) haven't. They begin to look dehydrated and there are no signs of root growing, altough they have (Maxillaria) new shoots (latents). I'm afraid they become completely dehydrated and die. Any suggestions?
Thanks in advanced and good greetings from Barcelona!

[trdyl]

Welcome to OB!

They might respond to water culture.

[dounoharm]

sounds like you are doing everything right....i would give those catts more time, they obviously went into shock, and are being stubborn.....gl!

[Masdyman]

You could also try KLN rooting hormone for a couple of months , are you spraying enough ?
I would imagine your temperatures are very nice even in winter ? so may need to mist more

I have just re -read your post you say it has been a month since you got the plants ,this isn't long so hopefully you should see them pick up over the next 6 months .
I would give them KLN though for a few months .

[drosera]

Thanks guys for your replies!
May be I should be more patient.
Trdyl, how do they respond to water culture if they don't have viable roots? May be I should mist more often, like Masdyman says?
I use Superthrive... I thought that it is like KLN hormone.
My main worry are Maxillaria and Odontoglossum species, cause they seem to be more and more dehydrated.
Thank you very much.

[trdyl]

You can use Superthrive or KLN. They are both contain a rooting hormone.

If the rhyzome is constantly touching water it will absorb some water not very well but it does slow down dessication. A few years back I recieved a Cattleya division with dead roots. After a few weeks of the rhyzome barely touching water with Superthrive it started to grow and put out new roots.

[Nico]

I know someone who put a rootless catt into water until a few roots grow and then moved it to s/h. Like Ted said before, water culture seems to help! Good luck!

[Lars Kurth]

You are doing all the right things: one thing you can do to rehydrate the plants is the following. Get some molasses or natural sugar. Dissolve a teaspoon in about 4 litres of water. Submerge the leaves of the plants for a few hours in the solution. The plants will absorbe carbohydrates through the leaves and rehydrate. It can give the plants enough of a boost to pull them through.

The key is to wash the plants thoroughly afterwards, as any suger residue will later cause problems with ants, mould and fungus. It's also a good idea not to get the solution onto the rhizomes. Maybe repeat the treatment after 2-3 weeks.

I would only recommend to do this for plants that are unpotted: getting the sugar solution onto the substrate will ensure that the substrate breaks down too quickly and may promote fungal disease.

Lars

[Masdyman]

Originally Posted by drosera

Thanks guys for your replies!
May be I should be more patient.
Trdyl, how do they respond to water culture if they don't have viable roots? May be I should mist more often, like Masdyman says?
I use Superthrive... I thought that it is like KLN hormone.
My main worry are Maxillaria and Odontoglossum species, cause they seem to be more and more dehydrated.
Thank you very much.

I would mist on a daily basis .

[drosera]

Thanks a lot.
I mist daily but may be I will have to sumerge the leaves or the plant.