Understanding Temperatures

[Petalsgalore]

I am getting back into orchids, just a little. I raised quite few years ago, but discovered it was hard to keep them humid in a house in the winter in Iowa. I now keep an average of 1,500 Clivia plants all over my house so I have to limit my orchids to a south bay window. My question is I have been looking at the Orchid Encyclopedia on line and they always have the temperature ranges like warm to cool or cool to hot. Could some one explain what this means. Thank you

Julie

[estación seca]

Welcome to the Orchid Board! I suspect with a few Clivias in the house you might have some extra humidity. We have an Off Topic forum for people to post photos of their other flowers... hint hint hint!

Cool C Intermediate I Warm W Hot H refer to night temperatures for most of the year. Some orchids are in between such as C-I or I-W. A few orchids grow in very wide temperature ranges. Hybrids tend to be much more tolerant than species.

Orchids can often, but not always, tolerate somewhat to considerably higher daytime temperatures. A lot of orchids, but not all, can tolerate cooler night temperatures than usual during the winter, especially if they are somewhat dry. But a lot of plants should never dry out completely.

A lot of orchid vendors show this information on their Web sites and you should always look for and read what your vendors say about growing their orchids.

A very rough estimate would be (remember these are night temperatures)
Cold 40F to 45F
Cool 50F to 55F
Intermediate 60F to 65F
Warm 70F to 75F
Hot 75F and up.

Humidity and air circulation matter, too. Cooler-growing orchids usually tolerate warmer night temperatures better if humidity is high. Tightly enclosed spaces without air circulation promote diseases, especially at higher temperatures than ideal.

Some orchids like a relatively constant temperature, while others do better with day-night temperature swings.

You can find most of this information for most orchids at various sites on the Internet dealing with orchids, and you can use the search function of this board to look up past discussions of particular kinds of orchids.

[Petalsgalore]

Thank you so much for such a detailed answer. You have helped me a lot. The orchids are in a south bay window which has lots of air circulation. My new ones ( miniature species) are mostly hanging. My cattalya hybrids and phals. are sitting down on the seat. I spay the miniatures daily as between the sun and air movement they dry out nicely. As fall turns to winter they will get more of a temp. swing between day and night. I will move the touchier ones further away from the window. As far as the Clivias, I sell them on eBay as well as around 500 of my own. This spring when they start to bloom, I will take you up on showing them off on off-topic. Thanks again.

Julie

[estación seca]

Be very careful with plants near a window during cold temperatures. Touching the glass can mean a completely frozen plant, and even a few inches from the glass can be fatal for some orchids. Some people cover the whole window with bubble wrap to insulate yet allow in the wan winter light.