So many of the plants we grow at home are from tropical, subtropical and rainforest regions, that it's often hard to get their atmospheric conditions just right. The best humidifiers not only help to humidify the air but clean it too, as well as being able to produce humidity at different levels for different plants.
In this guide, we’ll share some insight into why, how, and when to humidify your plants, as well as what to look for when buying the best plant humidifiers.
1. Elecameier Warm and Cool Mist Plant Humidifier
2. Elechomes Plant Humidifier
3. Hodgins Harvest Mini Humidifier for Grow Kits
4. Alicacho USB Mini Cool Mist Cactus Humidifier
5. Pagittr Ultrasonic Cool and Warm Plant Humidifier
6. HuPro Top Fill Cool & Warm Mist Plant Humidifier
7. Honeywell Easy-to-Care Filter Free Warm Mist Humidifier
Plant Humidifier Buyers' Guide
What is a Plant Humidifier?
Plant humidifiers are primarily used to increase atmospheric humidity in your growing space. They are useful for mature houseplants and tropicals, as well as native ferns when grown indoors.
Any plant that enjoys bright spaces, but appreciates moisture will generally be happier with a proper humidifier. Many gardeners use misters, or wet the foliage of their plants but this won’t actually humidify them, it just prevents moisture loss through the leaf.
For plants that need humidity, only a humidifier will do.
What to Look for When Buying Plant Humidifiers
Plant humidifiers are simple tools, so there’s only really a handful of things to check for when buying them:
Does the plant humidifier fit well into your room? If it doesn’t, you’re less likely to use it, enjoy it, or benefit from it. For small spaces, or shelving, check that your plant humidifier will actually fit where you need it as some can be really quite large.
Perhaps the most important factor when choosing a plant humidifier, is the space it can serve, or its range. Range isn’t just about the tank capacity, but the functionality of the humidifier unit.
Some humidifiers are designed to work within a few metres of the unit, while others produce further travelling moisture that can serve an entire room.
Energy supply (Corded or Charging)
Energy supply is important when choosing a plant humidifier. It’s rare to find a battery-powered one because they’re too finicky to use, but they are commonly sold as corded or charging (typically with micro USB sockets).
Corded humidifiers are much better, tend to cover a wider space, and do not need recharging. USB humidifiers can be used on charge, but the cords supplied are often just 1ft long, and charge tends to last for about 48 hours.
Different Types of Plant Humidifiers
There are three types of humidifier unit on the market; warm mist, evaporative and ultrasonic. Each has their merits, but they also have drawbacks, so make sure you’re using them for the right reasons.
Warm mist plant humidifiers
Warm mist humidifiers are great for large spaces, creating natural humidity, but should not be used in propagation rooms, as they can also increase the ambient temperature.
Their mist is less stable too, so when they hit cold surfaces they can cause damp, particularly if they are left on overnight.
Evaporative cool plant humidifiers
Cool mist humidifiers are great for warm room plants that like humidity but are susceptible to fungal problems (monstera, devil’s ivy, spider plants, etc.).
Evaporative cool mist humidifiers heat the water using electricity, producing occasional bursts of mist. They are great for poorly ventilated spaces as the moisture will fall, rather than standing on windows or cold walls.
Ultrasonic cool mist plant humidifiers
Ultrasonic humidifiers are more energy efficient, producing aerosolized water. They are excellent for ferns, but not great for tropical houseplants.
Keep in mind that the best plant humidifiers can actually function using all of the above methods, and the settings are easy to change, so spending a tiny bit more will leave you with extra options and a more versatile humidifier.
Best Plant Humidifier Reviews
Best Humidifier for Plants - Top Picks
Plant Humidifier Top Pick
Growing houseplants is, in many ways, inspired by the pursuit of beauty. It links as strongly with horticultural passion as it does with the joy of interior design, so your grow room accessories should match the style you’re after.
This warm and cool mist humidifier from Elecameier is stunningly beautiful and incredibly functional too. For any design-conscious gardener, you’re unlikely to find a better-looking humidifier.
Premium Choice Plant Humidifier
Elechomes produce exceptionally functional products, but it is rare that they look good too, so I was pleasantly surprised by this box humidifier, with a 5.5L tank and a range that would cover most open plant rooms.
The multifunctional humidifier works on warm and cool mist settings, so is ideal for the majority of houseplants, and just needs adapting to suit your needs.
Best Value Plant Humidifier
If all you want is something small, inconspicuous, and easy to use, then these mini humidifiers from Hodgins Harvest are fantastic. They sit neatly on shelves above, or within houseplants, to provide gentle cool mist humidity.
For a brand as well-loved as Hodgins Harvest to sell humidifiers like this for this sort of value is pretty incredible too, so you’ll be getting a bargain as well as a practical tool.
Plant Humidifier Frequently Asked Questions
What type of humidifier is best for plants?
Warm mist humidifiers produce the most accessible vapour without boiling the water. This creates fully Accessible and true humidity, as opposed to cool mist humidifiers, which produce aerosolized vapours – great for some plants, but less accessible for those that truly need it.
Are humidifiers actually good for plants?
Humidifiers are often criticised as an ineffective way to produce accessible moisture, but this is largely due to confusion between humidifiers and mister. Misters, either manual or electronic, produce a mist that settles quickly and simply wets foliage, preventing moisture loss.
Humidifiers support plants by improving atmospheric humidity, and keeping leaves humid but not wet.
Should I leave my plant humidifier on overnight?
Try not to leave plant humidifiers running all night long. They are more effective during the day and can cause mould problems when they are operated during cooler hours, partially during winter.
Aim to use them for longer in summer, and less frequently in winter. If your plants are dormant (deciduous or tender herbaceous) over winter, turn them off entirely.
Is tap water ok for plants in a humidifier?
Tap water is the best water source for plant humidifiers. While most plants prefer to be watered with rainwater, tap water will help the longevity of your humidifier unit.
Do plant humidifiers cause mould?
Plant humidifiers will cause mould if placed in the wrong room, or too close to a cold wall. Like any moisture in the air, they require ventilation to function safely and actively improve air quality in that situation.
In poorly ventilated or cold rooms, they do often cause damp and mould.
Do plants humidify rooms?
Some plants actually humidify rooms by themselves, particularly parlour palms and spider plants, that lose moisture through their leaves. In warm spaces, that moisture is released as vapour, in cooler spaces, you’ll often see water dripping as droplets from the leaf tips in the morning and evening.
How do you make a DIY humidifier?
In reasonably well-ventilated, well-lit rooms, you can make DIY humidifiers that are largely focused on one plant. All you need is a drip tray, some pebbles, and some water.
Fill a tray or plate with pebbles or gravel, and add a shallow layer of water to the base. On warm days, this will naturally provide humidity to plants sitting on top of the tray.
If you have a grow tent, be sure to see our product review and buying guide for grow tent humidifiers.
Get the Best Plant Humidifier for Your Indoor Plants
Plant humidifiers have been around for decades, but they are catching up with plant science really quickly. They are no longer just misters, wetting foliage, and fostering fungal problems.
Now, instead, they build atmospheric conditions that can closely match the natural habitat of your house plants. If you’re truly looking for the best plant humidifier for your home or office, then follow the guide above to find what you’re after.