Repotting large cymbidium
 

I have a large cymbidium in about a 16" pot - when I repotted it about 3 summers ago, I just moved it to a bigger pot and it bloomed beautifully 2 winters in a row. However this year didnt bloom - It has 9 or 10 fat green p/bulbs and many dried ones. I can see about 3 spots that I could divide it - except I always chicken out when I cut things. Dare I divide it into 3? What kind of medium should I use? How many of the old dried up bulbs do I keep? It's almost too big to handle at the moment. so will have to wait until the weather warms up - March or April maybe. Any advice appreciated!

Linda, as far as cymbidiums go, I think that how you pot them is more important than what type of mix they're potted in. I usually grab whatever's on hand in the garage whenever one of mine needs repotting. Currently, I have one large hybrid that's growing in nothing but straight medium-grade coconut husk chips. Several others are growing in a fine bark and perlite mix, and a couple are growing in the same mix that I use for all of my other orchids (medium coconut chips, medium-grade pumice rock, chopped NZ sphagnum moss, medium Aliflor clay, and small charcoal). All of them are growing fine, regardless of what they're growing in. So don't worry too much about what you decide to plant them in. If your plant is currently dormant, now would actually be a decent time to repot it. Since most large hybrids (like the one you described) start growing soon after the late winter/early spring flowering season, your plant should be fine if you repot it now. And don't worry about harming it by splitting it into three parts. Cymbidiums, in my experience, are remarkably resilient plants. And by repotting/splitting your plant now, you avoid the stress it might experience if you chose to repot it during the warmer months. Early repotting means early recovery--and increases the likelihood that your plant(s) will be strong enough to flower next winter. As far as the number of leafless backbulbs to leave on the divisions goes, I would try to split the plant so that at least three green, fully-leafed growths and up to six backbulbs (or a ratio of two backbulbs for every green bulb) are included with each of the three divisions you end up with. But again, I don't think that these numbers are particularly critical. The important thing is to try and make sure that each division has a set of green, fully-leafed bulbs (for making their own food and producing the upcoming growing season's new growths) and a good root system of white roots along with at least a few firm old backbulbs (for helping the divisions get established quickly before they produce a new set of roots with the new growths that should be starting soon). After you've repotted your plants, water them thoroughly and then let them dry out before you water them again. And don't sweat it if some of the leaves turn yellow and fall off, along with a bit of shriveling of the old backbulbs; all of that is normal. Repeat this process of wet/dry conditions until you see new growths begin to sprout up. After that point arrives, you can probably start watering more liberally, especially since the weather will by then have started to warm up and the lengthening days will be providing the plants with more light. Your plants can probably due with far less fertilizer at this stage also--at least until the new season's growths are a few inches tall, and a new set of roots is starting to form, at which point cymbidiums become the greedy pigs of the orchid world. This is probably more information than you really wanted, so I apologize for the long-winded response. :-)

Best of luck with your project.

Steve

In principal I agree with Steve but of course have developed my own favorite potting media. Like to add that you should remove all old and decayed roots and try to have a few healthy roots instead of a lot of rotten ones and your pot should be big enough so the it has 2" around the bulbs for future growth. I like what this web site has to say Basic Cymbidium Repotting

Thank you so much both of you. That website you referred to is excellent!

Good point about the amount of space to leave for future growths. And Loren Batchman (sp?) of Casa de las Orquideas has lots of nice cymbidiums too--in addition to his very helpful information.

Linda,

If you ask 10 cymbidium hobbyists how they repot their plants you will get 11 (at least) :) answers. Each climate also has a different set of aftercare requirements. However, one change I would make in the suggestions previously made by Steve is not to have more than 1-2 rootless leafless back bulbs on a division of 3-5 green bulbs. I also would question the heavy watering after repotting as the cut roots are incapable of absorbing water until they heal.

You might also want to check the archives on this forum for more repotting ideas. Basically, use what you think will work best for you.

In any case, jump in and don't be afraid. Cyms are tough and hard to kill!

CL

wow! If i were you, i'd just repot it without dividing. Imagine how many flower spikes it would produce next season. wow! 16" pot!

Leave it to the young to think big on plant container size.:rofl: Down the road you are faced with a HUGE project that may take a block party to handle! I have been on the repotting/dividing side of more than one 1/2 wine barrel Cymbidium! The last one had been in the barrel 10+ years, took 9 strong bodies and a sterilized machete to break apart, and ended up with over 80 BBs and 30 divisions! There are other ways to get a beautiful display with a Cymbidium! :wow