Need Cymbidium potting advice - Orchid Board

mjf45322 · #1 08-01-2009, 10:42 PM

I was able to get a few cymbidium species plants.
Tracyanum, bicolor, aloforium, lowianum.
I grow in a greenhouse for the winter and house outside in a shade house in the summer.
I live in Ohio so its kind of cold here during the winter months.
I keep the greenhouse in the winter at night at 55.
How much water do these plants like and what kind of potting medium should I make up?. Straight bark, bark/perilite/characoal/sphag.

Can anyone reccomend a good cymbidium book to buy that would cover species as well the hybirds.
Thanks,
Mike
mjf45322@aol.com

smweaver · #2 08-04-2009, 06:44 AM

Mike, of the species you mentioned, only bicolor is a true tropical plant and will probably prefer something a bit warmer than the winter night temperature you mentioned. The others, however, will easily handle that (and, in the case of tracyanum and lowianum, actually might do better with temperatures a bit lower than that, especially if they're forming spikes and buds). Cymbidiums in general like lots of water, especially during the summer growing season (less so in the winter, but I still wouldn't let them dry out too much--not anything like a cattleya). They're also reportedly heavy feeders, although mine don't get any more fertilizer than the rest of the orchids and they grow and bloom just fine. As far as potting mix goes, that (in my opinion) is of less importance than other growing factors (light, water, temperature differentials, etc.). I generally try to grow them in small to medium-grade bark, coconut husk chunks, maybe a little bit of charcoal and pumice. But whenever I've bought one from a commercial grower it's always been in straight bark (usually the small-grade variety). So I think that they're pretty adaptable and not too picky about what they're grown in. Just remember that if you grow them in a coarse and open mix, they will need a lot more watering than if you grow them in a small or medium-grade mix. As long as you keep water out of the new growths until they're a few inches tall they should be okay (especially if it's warm out and they're getting good light and putting on a lot of new growth). Try not to overpot them. They might look a little ridiculous in water appears to be a smaller than ideal pot. But cymbidiums have vigorous root systems and they will quickly fill up a smaller pot with lots of white roots if you're doing your job right (and you can just pull them out of the pot at that point and move them up to a bigger one). There's a monograph book by DuPuy and Cribb that was written a couple of decades ago that's still considered a benchmark for cymbidium species. It's been out of print for years, but I think I remember someone on this site stating that Santa Barbara Orchid Estate still has copies for sale. There's also a book that I used to own by a couple of growers in Australia, Graham and Sue Guest. It covered mostly the hybrids, but contained a lot of interesting and useful growing information. You can probably find it on Amazon or maybe even EBay. One last word of friendly advice--I too grow in the Midwest, so don't be too anxious when the cooler weather arrives in the fall. Your cymbidiums (with the exception of Cym. bicolor) will appreciate those temperatures. I generally don't bring mine inside until it starts to drop down to the high 30s at night, and they all do just fine (at those temperatures, though, they don't like to be sopping wet, so you'll want to water early in the morning on days when it's predicted to be cool). Good luck with your new collection.

Steve

Cym Ladye · #3 08-05-2009, 12:03 PM

Mike,

You have gotten four species in two large temperature tolerance ranges with different cultural requirements as a result. Cym. aliofolium is a warm growing species and should be treated as the Cym. bicolor. Both these species are extremely sensitive to any temps below 45 F. The Cym. tracyanum and the Cym. lowianum are cool growing species and tolerant of 32 F but not for longer than 8 hours before damage is done.

Other significant differences include light, period of bloom and potting mix.

Cribb has released a new edition to the original monograph and it is available through Santa Barbara Orchid Estate. Learning where these plants grow naturally will aid you in interpreting how to best grow them in cultivation under your conditions.

Good Luck,

CL

smweaver · #4 08-05-2009, 04:51 PM

Good information, CL. I didn't realize that Cym. aloifolium is an exclusively warm-growing tropical species. I don't grow it myself, but I did find the information I provide in my previous post from the culture sheet for this species that I got from the Baker's website (Orchid Culture - Charles and Margaret Baker). Their data indicates that aloifolium's average nighttime temperatures in the winter months are in the low 50s. Guess it's a good thing that I haven't bought this one, as I wouldn't want to pamper it during the winter months by having to move it into a warm environment every evening. Oh, and sorry, Mike, for my former (and perhaps misleading) comments regarding aloifolium.

Steve

Cym Ladye · #5 08-06-2009, 03:11 PM

Steve,

Both coriacious leaved Cym. bicolor and Cym. aloifolium are best grown hanging high in a cattleya greenhouse for best results. The big problem then is the rank size of the plants and the foliage then shades all your bench plants

CL

orchids3 · #6 08-07-2009, 04:26 AM

Mike,
Where do you live? Have lived in three regions of the
US and would use a differant mix in each.

mjf45322 · #7 08-07-2009, 01:23 PM

I live in the Dayton, Ohio area.
Mike

orchids3 · #8 08-08-2009, 08:32 PM

I have good luck with a mixture of Stalite Gravel and Coconut Husk Chips. Stalite is heat expanded shale and is used to make precast concrete. Put in a few tbl spoons of crushed shell per gallon. It helps buffer the pH and give the plants a little extra calcium. I use 3 parts of gravel to 1 part of CHC here - but thats because I get so much rain. The plants are either in a shallow dish of water or my version of Semihydroponic - as they do in Australia. Aloifolium does pretty well in my shadehouse here in Florida but I find that it doesnt really like to be cold so it goes into the greenhouse in winter along with madidum. My bicolor makes it thru the winter ok so far. Remember its a lot warmer here than where you live.