Sustee Water Meter Directions & FAQ's

This little guy is a game changer for plant lovers. Sustee water meters take the guesswork and stress out of the biggest impact you can have on whether your plants live or die - water. Here's how Sustee works, how to set yours up, as well as Sustee FAQ's.

Save time and watch this video, or scroll down to the directions and FAQ's below. This video shows you how to get set up right away with your new Sustee...


Sustee Directions 

Slide your Sustee out of its packaging. It comes with the core already inserted, ready to go. 

If your plant needs watering:

Locate the two arrows at the bottom end of your Sustee. That's the level the soil needs to be between for Sustee to work. 

Sustee water meter how to directions


Before you water, insert your Sustee into the soil so it's within about 20cm of the plant and root ball (so for big pots, don't go too far away from the plant). Pop it down into the soil until the top of the soil is between those 2 arrows.

Water your plant as usual. Once watered, the window at the top of your Sustee will turn blue. The colour change will start as soon as 30 seconds, but can take from 3 minutes (for the small Sustee), up to 25 minutes (for the large Sustee) depending on your pot and Sustee size.  

Then set and forget!

Leave your Sustee in your plant and check the colour every so often. When the window has changed from blue back to white, your plant needs watering.

For plants that have been recently watered:

Don't water your plant again! Instead of risking over-watering, prime your Sustee before you insert it. First, locate the two arrows at the bottom end of your Sustee. 

To prime Sustee: Insert the bottom of your Sustee in a cup or container of water (so the water level is between those two arrows). Wait about 30 seconds for the window to turn fully blue.

Sustee water meter changing colour

The arrows show the level the soil needs to be between for Sustee to work. Once primed, 
insert your Sustee in your plant, so your Sustee is within about 20cms of the plant and roots (so in a big pot, don't locate your Sustee way at the edge, pop it in nearer to your plant).   

Set and forget! Leave your Sustee in your plant and check the colour every so often. When the window has changed from blue back to white, your plant needs watering.


Sustee FAQ's

Where can I buy Sustee?

From me at Love That Leaf. Available in 3 sizes, in White > or Green >

Can I use one Sustee for multiple plants?

Yep! Although it makes it harder to monitor each plant's health if you're moving your Sustee around all the time, it is doable. It takes a day for the Sustee core to return to dry (white) once removed, so remove your Sustee, let it sit out and fully dry for a day. Check the window is white. Pop it in the next plant you want to check, following the directions above.

What size Sustee should I get?

The small is for your baby houseplants, for smaller pots sizes up to 10cm. The small Sustee needs to sit 4cm to 5cm deep in the soil. The medium is for the majority of our indoor plants, for pots from about 10cm up to 18cm. It needs to be inserted 7cm to 10cm deep into the soil. The large is for the big boys. For pots about 18cm to 36cm wide. It needs to goes down 11cm to 18cm deep into the soil. 

Sustee water meter size guide comparing small medium and large Sustee sizes to help you choose

How do I know when to water?

Easy! When the window at the top changes from blue to white. Blue = All good. White = Time to water! When you water, the core will change back to blue. Resist the temptation to water too soon, the window should be white (not half blue, 3/4 blue etc).


Image showing Sustee water meter when white and when blue to show when to water

What if I get my Sustee after I've just watered my plant?

Don't water again! Prime your Sustee instead. Follow the directions above or watch the video at the top.

Where do I put Sustee in the pot?

Pick a spot within 20 cms of the plant, then insert down in the soil, to the level between the two arrows. Watch the video or see the directions above.   

What types of plants can Sustee be used on?

All plants, because it's the soil not the plant that matters. If your plants are in a substrate that doesn't hold moisture, Sustee won't work. It needs soil or substrate that retains some level of moisture. Potting mix, peat, moss, bark... all good. 

I watered and my Sustee didn't change colour

This is usually because your plant needs more water. Sustee should go back to blue within 30 minutes of watering (small takes about 3 mins, medium 15mins and large up to 25 mins).

Check you pour enough water in so it drains out the bottom of the pot, or give your plant a good soak from the bottom (for at least 10 minutes) to make sure water's actually reached the roots and saturated the soil. 

Unless something's blocking your Sustee or your core is old, it will change to blue. Also give it enough time (see below for normal times).

My Sustee is blocked

Sustee sits in your soil, so for denser soils, older or hardened soil, or rootbound pots, the area at the bottom where Sustee reads the moisture in your substrate could become blocked or clogged. To fix it:

When first inserting the Sustee in to hard or oil soil, loosen the area you're going to insert your Sustee in. Or if you've had your Sustee in for a while and it seems clogged or blocked, take it out for a warm bath. Mix a little detergent with warm water. Fully emerge your Sustee, window end down, and let it soak for an hour. Take it out and anything blocking it will have been cleaned off. Dry it off and continue using as usual.

How long does it take for Sustee to change to blue once watered?

When priming Sustee in water it takes about 30 seconds. When it's in a pot that you've just watered, the small Sustee takes about 3 minutes to fully change to blue. The medium is about 15 minutes, and the large can take around 25 minutes. It will start turning blue sooner than that, but will take longer to fully return to blue. The times above are an average guide. For older or harder soil, and soil with low moisture retention, colour changes can take up to an hour.


How long does a refill last?

Ages! About 6 to 9 months on average. Your Sustee comes with the housing (which is reusable) and one core already inserted in the housing, ready to use.

How do I know when I need a new refill?

If Sustee shows no reaction at all but is not clogged or blocked, and you've had to about 6 to 9 months or longer, it's likely time for a refill. 

Are the core refills recyclable?

Yes! Keep the housing. It's reusable. Don't throw it away! The core inside is made of natural fibres which can be broken down by microorganisms.


How do I change the core?

Take your Sustee out of pot. If it's clogged or blocked with dirt, give it a clean first (follow the directions above). There are 3 components inside your Sustee, the core, a blue sheet and straw. It's not likely - but still possible - that the straw could get left behind inside the housing. If this happens, remove it with a pair of tweezers.

Remove the top and bottom screw caps. Pull out the old core. Insert the new refill core. Put the caps back on and off you go. Watch the video at the top from the 3 min 30 sec mark to see how to change it.

When changing the core, take the new core out right before you need it. If you do it too early and it discolours it won't impact it's ability to read water or how long it lasts. 

Does fertiliser affect Sustee?

No, unless used in excess of the correct dosage, or if the food or fertiliser is particularly oily, it should not have any affect on your Sustee.


Keep your Sustee out of reach of young children and animals. Sustee is not a toy and should not be put in the mouth.  

FREE shipping for orders $80+
Pay later Afterpay & ZIP
100% NZ In stock in NZ ready to ship
Fast delivery 1 to 2 days for most of NZ
FREE Shipping For all orders $99+ shipping NZ wide
Pay later Afterpay and ZIP available
100% NZ NZ owned. All in stock locally.
Guaranteed :) Anything wrong I'll put it right