Lucky for us, passionate gardeners, the vast majority of indoor plants are perfectly happy in average humidity within a home. This means you won’t have to bother a lot adjusting the plant humidity levels.
On the other hand, when I say “you won’t have to bother a lot”, that doesn’t mean you won’t have to bother at all.
It might just happen that you are a proud owner of some rare species native to tropics and sub-tropics. Those, as you are familiar with, require a specific amount of humidity. Or, your place may be crowded with succulents and cacti, which, as we all know, prefer drier air.
For that reason, I came up with this general guide on humidity, to help you solve some of the most common doubts. Here I shall tell you more about ideal indoor humidity, discuss what is low and what is high moisture, and how to adjust humidity levels in your home.
Stay with me and enjoy!
Optimal Plant Humidity
We all know that central heating or similar means of heating is the “No1 enemy” of humidity level. During the colder months, when the heating is continuously active, the air is significantly drier.
Even us humans are sensitive to that, let alone plants.
But, don’t despair immediately, you can solve it!
There are many ways to deal with this situation, and adjust the conditions so that your plant or plants don’t suffer.
So, your initial task is to have a better understanding of the different humidity levels and categorize your green friends based on those parameters.
How to define relative humidity (RH)?
This indicates the moisture level in a room. What you do is measure vapor and a specific amount of air including the water particles found in that particular amount of air. The result is RH.
These parameters are quite helpful. You use them to define the levels of moisture in the air which is comfortable for human beings, animals, and of course, plants.
Pro-Tip: Bear in mind that temperature plays a significant role in the moisture level. The higher the temperature and the lower the vaporization, and consequently- the humidity decreases. And vice versa, increased levels of humidity result from the lower temperatures and higher vaporization.
What Are Ideal Humidity Levels for Various Indoor Plants?
To make it easier for you to evaluate where do your plants belong, I came up with this convenient ideal indoor humidity chart. This should help you categorize your plants well, and understand their specific needs much better.
80% – 90%: This extremely high level of humidity is typical for tropical weather. You won’t encounter such high levels in other regions. If you possess some plants which thrive in such a moist environment, I suggest growing them in a greenhouse or glasshouse. If everything is done well, the humidity can reach above 80%.
60% – 80%: This is some sort of heaven for tropical plants, but truth be told, it’s difficult to maintain such levels of humidity in house. Tropical species are sensitive when the level goes below 70%. So, if you want your tropical beauty to be happy, you’ll have to boost humidity somehow.
60% – 40%: Great news for you is that 60 percent humidity in house is what the majority of commonly kept indoor plants adore. This belongs to “you don’t have to bother a lot” scenarios. Occasional misting is what will help you achieve the desired level.
10% – 40%: These are considered to be very low level, where the air becomes notably dry. This is mostly the issue during colder months- blame it on central heating. If you have cacti and succulents, they will be more than happy. However, the rest of the plants won’t be happy with these conditions. They will experience various issues, mainly changes in leaf coloration- yellowing, browning, or wilted leaves, and similar issues.
Pro-Tip: You probably wonder what kind of superpowers do succulents and cacti have when they have no problems with relative humidity below 30%? The secret is in their thick leaves which preserve water, thanks to which they can withstand drier conditions for quite long.
How to Be Sure the Humidity Level is Good?
Creating your very own home humidity levels chart could help you analyse the plants you have and accommodate them based on their specific needs.
There’s one very useful gadget that can be your faithful companion in measuring humidity levels- a hygrometer. They are quite affordable, and trust me- will save you lots of troubles.
Now, I always like to stress out that observing your plants can help you spot any issues on time, and save the day. This logic can be applied to humidity as well.
Let’s discuss what happens in both scenarios!
Issues resulting from too low humidity
- Tips and edges of the leaves turning yellow or brown
- Flowers and leaves tend to wilt
- Dying flowers and foliage
Problems resulting from too high humidity
- Gray mold appearing on foliage and flowers
- Signs of rotting on stems and leaves
Now you know what is considered high humidity and what is considered low humidity. Moreover, you are aware of what are the common issues. What we can do now is see what can be done to maintain the best humidity levels.
Pro-Tip: These common signs can help you react on time and fix either low or high humidity. But if you’ve already done that, and your plant still seems to be suffering, examine other things- perhaps these changes are the result of bright light or over-watering.
How to Deal with Common Plant Humidity Problems?
To fix the above-described problems, you’ll have to implement a couple of useful methods that will maintain the desired the levels of humidity in your home.
Misting is not only one of the simplest “hacks”, but the most effective one. The results will be visible within half an hour, as your plant will react immediately.
Grouping plants is the second solution, and it is also very effective. This method relies on the laws of nature- what you do is imitate the conditions from plants’ natural habitat. The trick is in trapping the air and moisture between each of them. Of course, if you opt for this, make sure each plant has enough space around, don’t crowd them too much.
I don’t know if you are a fan of bromeliads, but having those within a room will contribute a lot to improving humidity levels. These cuties, known as high humidity plants, preserve water in the vase part of the plant, meaning they have more than enough moisture, so “sharing” with others won’t be an issue.
Palms, peace lilies, Boston fern, Spider plant, Orchids, Tillandsia, English Ivy- these beauties belong to plants that absorb humidity. In case you live in humid regions, they should be your choice.
Placing pebble trays is one more way to make the environment achieve ideal humidity in the house. All you have to do is put a tray full of pebbles covered in water under the container. This way, the roots won’t be soaked in water, and they will be able to collect the needed humidity.
Finally, a dehumidifier or humidifier for plants is quite a useful gadget, and an ideal solution if all the above-mentioned fixes fail to improve the situation and achieve the best indoor humidity.
Pro-Tip: If you have central heating, don’t forget to place containers with water in a room. This is both for your own and your plants’ health and will maintain a good humidity level during the colder months.
Now that you know what is a good humidity level and what is the simplest way to achieve the best humidity level, get down to business, and inspect your home.
Do you measure humidity in house? Have you already created your very own indoor humidity chart?
If you have some special tips and tricks to share with me- don’t hesitate. I’m always happy to hear from you!