louis14

The text clearly refers to the fact that work should be done in the morning so the propagator can reach the "target" 50 degrees in the afternoon and heat up the sawdust enough so it does not go "under" (that word is missing in the text) 25 degrees at night. "Monter à 50°C dans la journée sous la cloche plastique permet de ne pas redescendre (sous) les 25 ° C la nuit".

This does not alter the fact that our Kluai Hom Tong plantlets grow out of the sawdust, into the 45 degree air of the propagator, developing 3-4 leaves and reaching 30-40cm height within a couple of weeks, looking as healthy as can be. Of course this temperature is not constant, but putting up with such a high temperature during 4-5 hours of the day does not seem to affect plantlet development in any way.
Once more, this is based on effective growing, in natural conditions, on a functioning plantation. Any need for fans, artificial cooling of any kind would be economically unsound for this simple propagation technique which is promoted to help low income farmers.
Finally, April and May are our two hottest months, things will cool down a little after that.
I'll post a progress report on our new propagation boxes in a week or so, I am waiting for them to look good.