Spider plants are one of the more popular houseplants to keep as they’re known to thrive in a wide variety of conditions, but do spider plants like humidity?
Spider plants thrive in humid environments, with humidity ideally between 50% and 70%. They will tolerate lower humidities, however, but this is not ideal if you want your plant to grow happily.
Interested in learning more about spider plant humidity levels and what you can do to ensure your plant has the ideal humidity for growth?
Spider Plant Origins
Spider plants are native to coastal and tropical areas of South Africa.
In these areas, humidity tends to be higher, naturally, and this should be replicated at home for the best results in growing a spider plant.
Keep in mind that spider plants are incredibly versatile. My spider plants have grown at a moderate rate over the past few years with humidity on the lower end of the spectrum (between 40% and 50%).
How To Increase The Humidity Around A Spider Plant
There are several easy ways to increase humidity for your spider plant.
Pebble trays are one of the most cost-efficient methods for improving humidity.
All you need to do is find a tray larger than the container that your spider plant is in. Fill the tray with pebbles or small rocks so that the spider plant’s container can be placed on them.
Add water to the tray so that the gaps between the rocks are filled with water, up to about half way or three-quarters in volume. As the water evaporates slowly it will increase the local humidity around the spider plant.
Humidifiers can be pretty expensive and are definitely the most expensive option for increasing humidity for your spider plant.
The benefit of using a humidifier is that the humidity can be taken quite high and will remain consistent. I would only recommend a humidifier if you have several houseplants that require high humidity, such as anthuriums.
Some areas of the home have higher humidity naturally, such as kitchens and bathrooms. As long as the other conditions (such as sunlight) are good for spider plants in these locations, sometimes all you need to do is place it in a different area with higher humidity for it to thrive.
I personally like to place my spider plants in my bathroom as this has a higher humidity level throughout the day.
Another thing you can do is place your spider plant next to another spider plant(s) or another humidity-loving houseplant(s). As the plants transpire it will create a mini-climate where the humidity will be higher than usual.
I place several of my spider plants close to each other for this very reason.
Should You Mist A Spider Plant?
Misting is quite controversial in the plant-keeping community.
Most plant shops recommend misting plants when you purchase a plant from them, alongside selling their own misting product. I personally avoid misting, however, and this is something I have spoken about in other articles as well.
Misting only increases humidity in the short term (a couple of minutes at most), and if you want to see a consistently heightened humidity from misting you would need to mist very regularly. It also promotes bacteria and pests, especially when the humidity is already high and the droplets from misting gather on the surface of the plant.
I recommend using one of the tactics mentioned previously to increase humidity rather than misting.
How Humidity Affects Spider Plants
Humidity can have some drastic effects on spider plants if it is either too high or too low.
If the humidity is too high, for example, it becomes much easier to overwater the plant which can lead to root rot. If the humidity is too low the leaves will dry out and start to curl.
Signs The Humidity Is Too Low
It’s much more common for the humidity to be too low for a spider plant rather than too high, as they prefer higher humidity levels. Low humidity causes a few key problems for spider plants.
Slow Overall Growth Rate
Lower humidity can cause a slow overall growth rate of spider plants.
This happens because the stomatal openings minimize in low-humidity environments to prevent water loss. As a result of this photosynthesis is reduced, which reduces growth.
When the air is drier, or less humid, transportation speeds up due to the difference in moisture content.
As a result, the leaves will lose moisture which causes them to curl up. This also results in leaf edges turning brown and becoming crispy.
Direct sunlight can be great for dealing with high-humidity environments (more on this later), but it can also make the humidity too low as it causes excess moisture to evaporate.
If the humidity is too low due to sunlight it will likely scorch the leaves as well. Just as humans get affected by direct sunlight, plant leaves can also be affected, and this will cause yellow spots which turn brown and eventually kill the leaves.
Signs The Humidity Is Too High
It’s very unlikely that the humidity would be too high for a spider plant, but it is possible in niche cases and it is characterised by a couple of symptoms.
High humidity can cause excess water to form in the soil and on the leaves of a spider plant.
Excess moisture attracts pests such as aphids and spider mites and can become a haven for bacterial or fungal growth. Root rot, for example, occurs when the soil becomes saturated with water and slowly kills off the roots of the plant.
Too much humidity can directly affect transpiration and slow down the overall growth of a spider plant, just like humidity levels that are too low.
This usually occurs as the roots struggle to process water if there is an excessive amount in the soil.
Yellowing leaves are one of the most common symptoms of overwatering, which is likely to happen if the humidity levels are super high.
The Best Way To Monitor Humidity Around A Spider Plant
Knowing the signs of low or high humidity is useful, but it’s even better to use a hygrometer to measure the humidity.
This way you can be certain of the humidity level, rather than relying on symptoms. Some symptoms can be signs not only of wrong humidity but other issues that may be affecting the plant, such as wilting leaves being a symptom of both low humidity and also overwatered soil.
Hygrometers can be purchased from most retailers at quite a cheap price, and they’re a good investment if you have multiple houseplants that require specific humidity levels.
Care For Spider Plants In High Humidity Environments
In high-humidity environments, you’ll need to treat your spider plants slightly differently than usual to keep them healthy.
Water Less Frequently
In humid environments, it’s important to reduce your watering schedule, as less water will be lost via evaporation.
Instead of watering once every week consider once every two weeks instead. Monitor the soil – I like to check the top couple inches of soil and if they’re dry I’ll know to water the plant.
You already know my opinions on misting, but it can cause some serious problems if you mist while the humidity is already high.
The water droplets will not evaporate easily, which can mark the leaves and also cause bacteria to grow. It will also attract pests, and frequent misting can lead to overwatering as well.
I avoid misting completely, but definitely give it a miss when the humidity is high already.
Use Direct Sunlight
Although spider plants prefer indirect sunlight, a few hours of direct sunlight per day can be useful in humid environments as it will increase the rate of evaporation of water which can help to prevent issues like overwatering.
Slowly increase the exposure to direct sunlight over the course of a few weeks and watch out for sun scorch.