Horticultural tips: ensuring the right moisture content for your tropical plants
This week we continue the series with Cécile de Ortigreen. We discussed the best tips for finding the right plants a few weeks ago. Today, we tell you all about the best ways to ensure good air humidity (hygrometry) for your tropical plants.
What is the ideal relative humidity level for tropical plants? What about cacti and succulents (succulents)?
For tropical plants, the ideal is to have a hygrometric rate between 80 and 100%. I get it in the summer in my outdoor greenhouse with my ultrasonic mister. A real tropical jungle! Otherwise, I would say 60% is a good humidity level for tropical plants.
For succulent plants, 30 to 45% is sufficient, but it also depends on the variety. Some plants can tolerate a higher level of humidity if the substrate remains dry. On the other hand, some cacti can stay dry between 5 and 1 degree Celsius with very low humidity (below 30%). It is then their period of rest.
All in all, the ideal for plants is difficult to live with in our apartments!
What's the best way to ensure that the air humidity is high enough?
Group your plants together! Plants naturally release moisture, so they provide each other with moisture naturally.
You can also protect your more drought-sensitive plants, such as ferns, by surrounding them with more resistant plants.
Otherwise, the freezer bag method for small plants is very effective if you don't forget to check them regularly! For larger plants, transparent plastic boxes can make a good terrarium for cheap. If you have a better budget, a real terrarium with integrated Biorb light.
Finally, a good humidifier or mister with a mini fan (which I use) is very effective!
What do you think about water-filled clay bead beds?
I use the clay balls watered in the cups of my colocasias and papyrus. They need to be in water permanently!
What about daily spraying of the plants?
I don't think this is enough to increase the humidity in a room. Spraying has a very short-term effect. It is therefore not enough for tropical plants that need humidity all the time. On the other hand, even if spraying has little or no effect on the humidity level, it prevents attacks by water-hating mites!
What is your opinion about greenhouses?
They are still the ideal place for tropical plants to grow. They provide good ventilation, controlled humidity and constant warmth. These factors are the keys to growing tropical plants indoors.
After how many plants do you naturally reach a high enough humidity level?
This depends first of all on the size of the room.
If a room is large and the number of plants per square metre is low in ratio, it is obvious that the humidity in the air will be lower, because the number of water particles per m3 of air will be lower.
It also depends on the foliage present.
Large leaves release more water molecules into the air as a result of evaporation and transpiration than small leaves. However, a large number of small leaves per square metre can release an equivalent number of water molecules into the air.
In the end, it depends on the pots used.
Once the terracotta is wet because of its porosity, water molecules are released into the air and naturally increase the humidity.
What should we remember about the ideal humidity level for our tropical plants?
Maintaining a humidity level around 60% seems to me to be good for the survival of tropical plants. Moisture is essential for the survival of a tropical plant, especially in winter! Finally, the purchase of a hygrometer, or even several, as simple as possible, offered at 4 or 5 euros ($6 or $7 Canadian) depending on the room, is strongly recommended!