Crew 3-in-1 Water Meter - Light pH and Moisture Soil Meter - GREEN

"Worth purchasing. Great instructions given, saved a plant from over watering, sometimes the finger test just isn’t accurate enough. Should have stopped mucking around and purchased one!"
Liz Hosking ⭐⭐⭐⭐⭐

These 3-in-1 Soil Meters combine a soil moisture meter, pH and light sensor all in one (although most planty people get it just for the water setting). A super-affordable tool for peace-of-mind when used alongside other signs your plant needs watering. Superb for checking where you can't reach to find out moisture level down at root level, especially handy for deeper or larger pots. This is for the GREEN.

 AVAILABLE COLOURS  Green (dark forest green), Black, Mint  (a pale minty sage) and White  

How accurate are 3-in-1 water meters?

Despite the super low price, they actually do a good job. Plus you only need one for your entire houseplant collection. Of course they're not as accurate as the much more expensive, professional meters - and these don't last forever - but they are a good guide, especially to check moisture levels down by the roots where it really matters to help avoid causing root rot. Great for peace of mind to help you avoid over-watering and for checking deeper or larger pots.

No batteries required

The meter and probes work like a battery, but with no batteries required. The 2 probes are 2 different types of metal. When you add an electrolyte (that's the moisture in the soil), it works like a weak battery, sending a signal between the 2 probes, with enough 'voltage' for the sensor to read. The less water in the soil the less voltage goes through the meter. 

Can you leave them in the plant?

 USE AND CARE   Never leave these types of meters in the soil. Always wipe the probes down with water then dry them after use and store dry. Ideally wipe with distilled water if you have it as that reduces mineral salts building up. If you want the type of meter you can leave in the soil, have a look at the re-fillable Sustee or biodegradable, plastic-free PlantDoc instead.

Do they last forever?

These types of 3 in 1 soil meters will eventually need replacing. They won't last forever. You can tell when to replace them by the metal probes. The tips and the probes will be affected by water and salts in the soil over time and the metal surface will show salt build-up, erode and discolour. Proper care will extend how long they last (see USE AND CARE above).

How to use a 3 in 1 meter to check soil moisture

Push the switch far left to the MOIST setting. Push the sensors deep enough in the pot to reach root level near the bottom. Wait a minute or two to get the reading.

 HOW TO READ THE DIAL  There are 3 zones: 1 to 3 is the dry / red zone, 4 to 7 is the moist / green zone, and 8 to 10 is the wet / blue zone. Water according to your plants preferences. Getting multiple readings is normal as water won't be evenly distributed, so take a few readings around the soil. 

 RESULTS  Keep in mind these work indoors and outdoors in a range of soils (check FAQs below for soil types before you buy). That means, unless you've got an indoor plant growing in the same fine, dense, high water-holding soil you would use outdoors; a 'wet' reading should be unusual for most indoor plant soil. Plants that love moisture are an exception, like Peace Lilies in finer soil. I'll email you a few simple tips after you order for things to do (and not do), to get the most accurate readings.

My favourite benefit is the length of the probes for checking moisture where fingers can't possibly reach, down at root level near the bottom where water collects. I've had lots of times where plants I thought were dry, and would have watered, turned out were still wet down at root level.

For indoor plants: Pay attention to the ZONE on the dial (dry, moist, wet), rather than the exact number.

I find these super handy if you're not 100% sure and worried about over-watering. I did find the probes need to go down at least 10 to 12cms or more for better readings (the length of the probes is 17cms), so if you mainly have plants in small pots, get the shorter Soil Sensor, or Sustee or PlantDoc instead.

How to use as a light meter

Move the switch to the middle setting by the word LIGHT. There's a small light sensor panel at the front of the meter. Face that towards the light source in the same spot you plan to put your plant. No need to wait, you'll get an instant reading on this setting.

 HOW TO READ THE DIAL  0 is Dark. From 200 to 1000 indicates low to medium light. 1,000 to 2,000 is the medium to bright zone (direct sunlight registers over 2,000).

 RESULTS  The dial ranges from 0 to 2,000 lux but what we call medium light indoors registers in the dark zone. That's because this meter is made for both indoor and outdoor use. Indoor readings should be in the low to medium range even in bright indirect light. Direct sunlight will read in the bright zone.  

How to use as a pH meter

Move switch to the setting on the right, by PH. Put the sensors quite deep in the soil. Wait about 10 minutes for the result to show on the pH dial. The dial goes from ALKALINE (8) down to ACIDIC (3.5).

 HOW TO READ THE DIAL  I use my 3 in 1 meter primarily for the moisture meter setting, so wasn't expecting amazing accuracy from pH (or the light settings), but it was more accurate than I expected.

Use this setting as a first alert if your soil swings too far acidic or alkaline, then investigate further if needed with a more accurate meter (there's a reason pH meters cost far more than this meter!). My own indoor plants test in the mid-5 to 7 zone.

FAQ's to know before you buy

 NOT FOR ALL SOIL TYPES  It may seem obvious once you know how they work, but the substrate type matters, because the probes need to measure the water content IN the substrate. the probes can't break their way INTO some substrates like chunks of bark or inside balls of leca, so will give you a dry reading in very chunky, airy mixes. That's because the probes are measuring the air, not the substrate.

Great for the majority of standard outdoor and indoor potting mixes, from fine to medium grades. It's just very chunky mixes, like medium to large grade bark-based potting mix (like orchids are often in) that don't work with these and most types of moisture meters.

 MEASURE WET SOIL FOR pH   Only measure pH in freshly watered soil. Drier soil doesn't give accurate pH readings. 

 GUIDE NOT GOSPEL  Remember ALL moisture meters are only a guide, not gospel. They don't know what type of plant they're in. Moisture meters can only tell you what the moisture level is where they are in the plant, not when to water. You still need to decide when to water according to your plant's needs and your conditions. Moisture meters are a tool to help you read the signs. Don't ignore your plants other signs they need water, such as wilting.