Overwintering plants - Relative Humidity

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el48tel
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Re: Overwintering plants - Relative Humidity

Post by el48tel »

ralphrmartin wrote: Mon Dec 10, 2018 11:59 am My plants are doing just fine in conditions where the RH can go up to 100% after rain, or as the temperature drops.

However, I do have fans which come on when the RH is over 90%, to try to help prevent botrytis etc.
Ralph
That actually raises my hopes of success ---- immensely.
Endeavouring to grow Aylostera, Echinocereus, Echinopsis, Gymnocalycium, Matucana, Rebutia, and Sulcorebutia. Fallen out of love with Lithops and aggravated by Aeoniums.
Currently being wooed by Haworthia, attempting hybridisation, and enticed by Mesembs.
N.D.
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Re: Overwintering plants - Relative Humidity

Post by N.D. »

el48tel wrote: Mon Dec 10, 2018 2:06 pm
N.D. wrote: Sun Dec 09, 2018 11:18 pm What is the minimum RH for mesembs that would be OK during winter?

My problem is low humidity. My mesembs are kept indoors over winter. It is way too warm for them indoors (especially once you shine some intense light at them), and I cool them by blowing outside air (at about -15C and 60%RH) onto them. In the process, the outside air warms up to +5...+15C. This brings RH down to about 10%. That's dry. Some plants shrivel pretty quickly, and I am not sure what to do about this. Watering many mesembs during winter is a bad idea.
Have you considered putting open bowls or tall containers of water interspersed between the plants to raise the RH?
I have. This is the first winter I am trying this set up. The problem with bowls of water is that this whole contraption is inside a box, so space is at premium. Another issue is that air is blown at a pretty fast rate over the plants (on the order of 100 cubic meters per hour). Water would have no time to evaporate and raise RH at this wind speed. If this RH proves to be insufficient, I would have to come up with a humidification system that would be able to dump massive amount of moisture into this box. I would probably have to hook it up to one of those ultrasonic humidifiers.
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