I have bought and placed orchids at various times of the year without troubles. You just need to know the idisyncrasies of your particular species.Rain_Frog said:Now is the time of the year to buy orchids. Only this time is good. Why? Because orchids should only be transplanted when they begin growing root tips.
Generally speaking, Phals are the ones that need to have 1-2 month periods where the night temps are at least 10-15 degrees cooler than daytime temps, usually into the mid 60's. They tend to grow well in terraria, but most I have are too large to place in terraria.Phaleonapsis is your best bet because they like it warm. Dendrobiums and others will grow too tall and need cool nights to flower.
The genus Dendrobium has incredible diversity in the care required for different species, as well as the size. Some will have canes as large as 6 feet tall. Some have canes as small as 4" at maturity. I like to try Dendrobiums from the sea level rainforests of New Guinea, Java, and other areas where it is hot and humid at all times, as that is similar to the conditions we provide. I have had a Dendrobium 'Emma White' in my terrarium for 3 years now, and it has flowered every 6 months without fail. It is beginning to get rather large, however (18" canes). If you are interested in orchids for the terrarium, consider doing some research on http://www.orchidspecies.com under the Bulbophyllum, Dendrobium, and Pleurothallid Alliance orchids. Phrags and Paphs can do well in terraria, also.