A super-affordable way to keep an eye on temperature and humidity to help create your plants happy place. This is for the BLACK digital meter, also available in white here >

Many of our indoor plants prefer things warm and humid, with humidity on the higher side, such as Philodendron (70%+), Monstera (60%+), Calathea and Pothos (50%+). This little digital meter makes it easy to know when your plants need a humidity boost when humidity levels drop (check out those H2O cordless humidifiers if you don't have a humidifier yet, my plants love theirs).

Especially worth keeping a close eye on over winter when cold temperatures combined with indoor heating zaps precious moisture from the air, leaving our plants with dry, crispy tips and edges, even when soil moisture is fine. Also when temperatures soar and plants need more humidity to help cope with the heat,

Is that price right?

Yep, sure is. Super budget friendly right? Save your pennies for your plants! But at this price, don't go expecting rocket scientist level accuracy. Thermometers and hygrometers can get into the hundreds. However I have been pleasantly surprised that something this cheap actually works really well. 

How accurate is it?

I wouldn't make life or death decisions by them, not at this price compared to some of the fancy pants expensive digital thermometers and hygrometers you can get, but they are so handy to keep an eye on general conditions and surprisingly accurate for the price. 

They respond within about 10 seconds to changes in temperature and humidity. My tests found them accurate to about one degree in temperature, and to about 5% in humidity. Definitely accurate enough to make heating and humidity decisions on.


Temperature is displayed in celsius to one decimal (eg: 20.5 degrees), and the range goes from negative 10 degrees to + 50 degrees. Humidity is displayed in round numbers (eg: 60%), and the range goes from 10% to 99% humidity.

Where can I put it? 

Pretty much anywhere! It's small (measurements below) and fully portable. I have one in each room that I have plants in (I just put them on my plant shelves). I wouldn't recommend leaving them inside a grow house or grow tank longterm though. It'll likely cause excess moisture to work its way in to the electronics or rust the battery. Once that happens the display might act up or it may stop working altogether.

Portable mini size - just 4.5cm 

They may be mini, but I find the numbers big enough to read easily, even without my glasses on. Plus at 4.5cms tall & wide x 1.5cms deep, the size is great to pop them anywhere and everywhere your plants are.

They are fully portable (no cord), and the battery's included (fits one LR44 battery, supplied). The battery is the same type used in watches and calculators. The photos show you the back with the battery cover removed, showing where the battery goes. The housing is plastic and the display is an LCD screen.

Important - Safety first

This product uses a button battery so should be kept out of reach of children and pets. Small batteries are a choking hazard. If ingested, there is also the risk batteries may cause burns or tissue damage. If you suspect your child or pet has swallowed a button battery, always treat it as an emergency.