Cattleya dividing and repotting "rules" and back bulbs

[ddivey36]

So I am inspired by Astrid and her question types:
Here I go...
I was given 5 cattleyas that are just beginning to crawl out of the pots...Bifoliate and unifoliate types.
*for both types when they are sprouting new growths and roots (which is now) should I cut off the front parts and repot.

What happens to the back bulbs? If I see active eyes, will those back bulbs reproduce, or do most cattleyas continue the front crawl and the back used up bulbs should be thrown away to make room for other plants...

I have done it both ways and some of my back bulbs cattleyas have reproduced and some I have had to throw away as they were spent.

Wondering what (realizing that each plant is different) the forum says....is it best to keep the front parts only? In general do catttleyas just crawl forward? What successes can you share? What advice in general should I follow? How do you know if you should keep the back part- if the active eyes are "hidden"...

I also divided an SLC Magic fire into 4's- AT THE WRONG TIME- was an experiment- 3 of the 4 parts are putting out new growth....the ugliest/oldest part has not....I probably should have keep this plant all together but was testing all those opinions out there about dividing....just had to try for myself....but now I have small plants that I may have to wait a year or two for a bloom, and not a specimen...BUT sometimes it is better to divide when the older part of the plant looks hideous?

Thanks for your comments and letting me ramble on...

[silken]

The best time to repot both unifoliate and bifoliate are when new root growth is just starting. Especially the bifoliates as they can sulk for a year or even longer if disturbed at the wrong time. There is no need to ever divide your Catts (or any orchids) unless you want to share them or they are just too big for any pots or your space. The old back bulbs continue to support and provide nutrients for the new parts until they are dried up and dead. It is easier to repot before the plants are crawling out of the pots as they will some times start growing downward making the newest most desirable parts of the plant difficult to pot up in new media with some of the old parts still attached for nutrient support. Most growths will have several dormant eyes that could start a new growth but usually they only put out new growths from the latest matured one. Often they can grow from several directions so that you have 3 or 4 or more new growths all at the same time, depending on plant size. This is how you get to have one of those awesome blooming specimens with multiple bloom spikes. It seems the larger the plant, the more and better it will bloom as those new growths have so much support.

If you are going to divide it, you should leave a minimum of 3 to 4 live growths on each piece. The old back growths often don't have many live roots left as they mostly grow roots when the the pseudo bulbs are new and developing. So taking a rootless older piece with no roots may not succeed unless one of the dormant eyes will develop quickly enough to get roots out there and growing into the new media.

[Fairorchids]

We all have a special plant, that is not dividing itself by setting multiple new leads voluntarily. To encourage the backbulbs to become productive, at least 6 months before you plan to repot, cut the rhizome with a razor blade, so you separate the front lead (min 3-4 mature PBs). That way, by the time you repot, you will know whether those BBs will do anything or not.

Do not use the same razorblade on multiple plants without sterilizing inbetween.

[tucker85]

I agree with everything Silken said. I'm not a fan of dividing cattleyas. Even though the plant only blooms on the new pseudo-bulbs, the older part of the plant stores nutrients and water and adds to plants ability to bloom. Large cattleyas with lots of p-bulbs will usually bloom much better than smaller plants. Of course there's always a limit to how large a plant can get before it no longer fits in our growing area. In that case Fairorchids makes a good point. You can cut the rhizome without unpotting the plant and wait for both parts to put out new growth before repotting. It doesn't always work but often it does.

[ddivey36]

Thanks and I agree with everything, it's nice to bounce off ideas with each other and it is good to have reassurance that we are going in the correct direction!