Humidity for desert cacti

[Salspi]

Hi
What is the proper humidity level for cacti in a greenhouse/indoor environment?
Thank you

[ElieEstephane]

I like to keep my desert cacti in the hottest sunniest place i can find that they may even sunburn a little. However that location is on top or next to my open water tanks where the humidity is quite high. That doesnt seem to affect them any bit.
I guess humidity is not a very important factor as long as you have good air circulation.

[Grimm]

I live next to the sea, where 60% is fairly normal. It makes growing in plastic pots more difficult as the level of transpiration and/or evaporation can be very low, but otherwise the plants don't seem to be bothered.

Additionally, some cacti rely on morning/sea mists, fogs and dew when they grow in the wild, so at least some will be used to occasional/daily high humidity. Others, such as whatever grows in Death Valley (I have read that there are cacti there, but I've never checked what type), probably never encounter high humidity in the wild. What I'm trying to say is that there is unlikely to be an ideal humidity level unless you have a very specialised collection of cacti from a single environment.

[Salspi]

Cool thanks. My humidity is always between 45-60%. I guess that is fine. My air circulation is strong.

[DaveW]

I don't think humidity is a problem in the growing season, but it can be in winter in the UK when plants are not growing since excess humidity coupled with cold it can mark some plants.

[TimN]

I think excess humidity might have the effect of making mold or rusts more likely. And, as already observed, reduced transpiration. That can allow molds and/or bacteria to grow in the soil.

Humidity in PHX today at 3 PM is 26% (probably the low point of the day). There are some clouds in the sky, humidity here is normally below 20%. Lowest humidity I've ever observed here was 3% about 5 years ago.