After the bath, humidity in the first days must be close to saturation and progressively decrease.
Most tropical plants acclimatize more easily at 18 - 20 Celsius rather than 35 C, and humidity, measured in gm of water vapor per cubic metre of air is better provided at 20 C rather than 35 C in temperate climates.
Too hot and too dry, they are twice penalized.
|Humidity in Stockholm, Sweden|
|Temperatures in Stockholm, Sweden|
The situation in Spain is just the opposite : the relative humidity in July falls sharply to 40 % while the heat is over 25 C and can even reach 32 C.
In Madrid on 3 July 2015 the humidity was only 19 % for 38 Celsius.
Las Vegas in the state of Nevada, USA, is even worse than Spain for the relative humidity and temperature relationship when tropical plants are concerned : the humidity goes down to an average 13 % in June !
|Humidity in Las Vegas|
|Temperatures in Las Vegas|
In a situation like in Spain, at 32 C and a humidity of only 40 %, 1 cubic metre holds 14 gm. The tent will have to hold 27 gm if the humidity has to increase to the higher level of 80%. The difference is 13 gm, only a fogging system would fast provide enough water vapour to allow the plants to smoothly brace themselves for the dryer environment a few weeks ahead when we open the tent.
In Geneva the relative humidity is high and even more steady than in Sweden.
|Humidity in Geneva, Switzerland|
Temperature and humidity in Roma ( Italy ) : from March to July the average temperature rises sharply but the humidity is very consistent throughout the year.
|Temperature in Roma|
|Humidity in Roma|
The chart below shows the relative humidity in Bangkok, Thailand : it is high and steady over the months of the year, more or less as it is in Geneva ( Switzerland ) in Sweden or in Roma.
|Humidity in Bangkok, Thailand|
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