Temperature

The temperatures that are suggested for orchids seem pretty prescriptive, but in reality they can survive in a much wider range of temperatures. The temperatures that are suggested for a certain species refers to the natural environment where they inhabit naturally (if they still exist in nature), as these temperatures represent the best chances of getting them to grow, thrive, and flower.

In reality however, not many of us can perfectly replicate the temperature range that every orchid in their collection requires. So compromises have to be made.

Here's some general guidelines:

• There is less risk of losing an orchid to cooler temperatures rather than warmer temperatures
• If outside of the temperature zones, be careful with watering. In cooler weather excess watering leads to fungal rot, and in summer it leads to bacterial rot among other pests.
• Balance off the temperature difference with light, e.g. apply extra shade when temperatures are high, and remove shade when temperatures are low
• Use airflow when temperatures are high to cool the leaves
• Provide extra humidity, when cooler the air warms the leaves as it condenses, and when warmer it prevents leaves from losing too much moisture due to transpiration. 

Weather Zones

A lot of literature recommends weather zones, e.g. US Hardiness zone 1-10 - these zones in particular refer to the lowest temperature possible in that region, but not the highest. For temperate areas this makes sense, but there are many parts of the world that can have extreme low temperatures and extreme high temperatures every year, in which instance these zones are not very helpful. Websites such as weather-and-climate.com can provide such data that can be compared against the temperatures recommended for the orchids you are growing.

You might use the monthly averages to determine where your orchids should be housed during the year, e.g. in hot climates move the cool temperature orchids in deep shade areas, or in cold climates move the warm temperature orchids indoors or to a protected area.

Tags

In a large collection it may be worthwhile to colour code your orchids with potting tags, e.g. orange tags for warm temperature orchids, blue tags for cold temperature orchids, and green tags for intermediate temperature orchids, this will allow you to group orchids by their temperature preferences and move them as needed when your climate changes.