It is impossible to say because each repot/divide situation depends on the plant.....
How many growing leads
How many fully leafed pseudobulbs
How many of the pseudobulbs have growth eyes
and so on.
Cattleyas tend to only make new roots from the front growth and they might make those new roots as soon as the new pseudobulb starts to grow or later when the the new growth is nearly mature.
A general rule is to try and get five growths counting back from the growing lead.
Even leafless pseudobulbs will grow a new pseudobulb provided they have live growth eyes at the base.
One technique is to cut the rhizome at appropriate places in the season before you actually divide the plant.
Sorry that this is the usual "it depends" sort of post but it might make sense with a little more research.

Thanks for a reply..
It depends on what?
I don't want to divide, just want to know how to repot with this cap of roots tightly wound around each other. I don't see any actively growing root tips, just six or so new pbs and lots of old but good roots,
I cleaned away the bad roots that were in the middleunder the mat, so I am just left with a semi circle of roots.

Do I push the plant down in the basket and pile the media on top or lift it up to the rim and put the media under, on the floor of the basket

Sounds confusing. Thanks.

It is confusing if I cannot see the plant and I am talking about 40 years growing experience and hundreds of "Cattleyas" in my collection. BUT nil C. amethystoglossa

20 pseudobulbs and how many growing leads?

Here is a simple to understand (i hope) example.
I have an in bloom. Blc. Momilani Rainbow 'The Gypsy'
Think of its current growth as a Capital Y
The RHS side tip pseudobulb has blooms.
The LHS side tip pseudobulb has buds.
The Bottom bit of the Y has old pseudobulbs,some with live growth eyes and nil roots.
Come spring I am going to divide the plant right in the middle of that y so that i get three divisions each with five or more pseudobulbs.
I am dividing the plant because it has outgrown its 14CM basket pot and I do not put plants into larger pods.
Two of the divisions should flower within a year while the back division consisting of mainly rootless old pseudobulbs will take longer to get to flowering stage.

As for where the roots go....i bury them under the mix.

So you can either repot or divide. it depends on where the plant is in its growth maturity Cycle.

As far as getting new roots goes. Hybrid Cattleyas vary when they grow new roots depending to some extent on their ancestry.

This post was edited by arthurm on Sat, Jun 15, 13 at 20:49

So just push all the roots that are wound round and round below the base of the pb into the basket and put media on top and the roots will uncoil themselves and grow into the media.
When will the new roots show? I see new pbs but no green tipped new roots
. I am not dividing the plant even though it is big. It is going into a basket and rehung.

I am trying to attach a pic of the plantwith roots at the base of the pb. This is not my plant but just imagine only the green roots from top right to left (more tightly wound round and round the rim of pot) and the center under green roots empty.
In my case the green roots on this pic are creamy on my orchid with no green growing tips.
The guy in this pic just put plant in basket and topped with media. His roots were under media; mine are exposed on top. Like they decided to escape the brown roots underneath,

Here is a link that might be useful: {{gwi:171965}}

Putting medium in the center of a plant with no roots can cause problems. The medium will stay wet and there won't be any roots to use it, and it will start to rot the roots around it. You might consider turning the plant upside down, filling in the rootless center with packing peanuts, covering that with a strip of plastic wrap, then turning the plant right side up and putting it into it's new pot. Gently pull out the strip of plastic wrap.

You're in Miami where it is hot and humid. You should be able to place the plant into an empty plastic pot until new roots start to grow, then pot up w/ your normal media. For me, C. amethystoglossa roots in the spring. Since I have ample warmth and humidity in Hawaii, I use the empty pot method for many Brazilian bifoliates that have poor roots or rootless with relatively good sucess.

Just shove everything in a larger pot and fill with good bark. Medium sized orchiiata is about the best available now. I add about 1/3 Perlite, optional After that just stand back, a big plant will look after itself.

Nick

Lord, I am afraid for this plant. This a.m. I looked at it and three of the leaves have soft spots, dark on them. I cut off and dusted cinnamon on the cut tips. Then sprayed with Thiomyl (Clearys 666). The leaves feel softish and have a colic-y look....like it is sick. The leaves are not hard and leathery like the others cats. I have it in the shade, because I read that bright light is too much or sun. I guess not having any roots to take up water is the reason why it is softish!!!????

I give up and am just going to leave it.
If it lives, it lives.
I am upset.

If you want to do the best for this plant, go back to it's origin. It's an epiphyte with the air-roots, exposed to air. It circled the inside of the pot and hugged the bottom because it was trying to get out, did not like it inside that pot. Same reason it has all those healthy roots outside the pot, doesn't want any part of being inside a pot.

Pull it out of whatever it's in right now and stuff it into a basket, either plastic or wood without bark or anything else. If all the roots don't fit in, let them hang over the edge. Then water it frequently and stand back, it will do just fine.

Nick

OK, I will do that, but what should I do if I see it shriveling, or losing leaves, or turning yellow or anything that these orchids do when they are dying?.

Just let it go..?
Can I put some rooting hormone on it>
Thanks for all your advice.

Use Holy Water and beat your fist on your abdomen.

nick

Here is a pic. (worth a thousand words) orchids in a shade-house placed in the sunniest spot in the garden. Full sun is too severe in the climate here but full shade is useless for most orchids and they will go backwards.
{{gwi:144194}}
Do some research on your orchid. Jay's species site is a good place to start. My impression is that your Cattleya has pretty large pseudobulbs and a 20 bulb plant would be huge, but maybe it has a lot of smaller growths because it started off as a baby.
Find out from local orchid growers what the optimum shade level is for Cats in Miami.
Do some more research, setbacks are part of the learning process.

Nick and Arthur are right on. Just put it in a basket and hang it somewhere in partial shade. I wouldn't fool with it. What will be will be.

Jane

Thanks for the compliment Jane. The only problem is that what works for me in my backyard with my watering habits and what works for Arthur, who does all of this upside down, making his success even more amazing, may not work in Florida. But I am convinced that if you mimic the natural lifestyle of a plant, it will probably do well.

Nick

Yes, there are problems in a lot of areas. When it is today here, it is yesterday there, and this feeling that maybe you could drift off into space at any moment....
But we do the best you can and having the seasons at the wrong time of year might actually be a blessing orchid show wise.
I hope the OP doesn't get too unhappy with this off topic stuff.

Thanks Arthurm.
No, I don't mind the off topic stuff.
I realise that everyone is trying to help someone who is whining about her orchid.
It does have a lot of baby growths that have popped out.
Thanks again.

Everything has it's pros and cons. We are blessed because our toilet water flushes in the right direction without any effort, you guys get to drive on the right side of the road. Which of course is the left side.

Nick

Baby growths are good. Plant is healthy.

Relax...

Jane