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All your questions about Sustee (that watering device)

All your questions about Sustee (that watering device)

You might have seen this new device popping up on your favourite plant-grams, or lusting over them at your mate's place, but what are they? and what do they do?

Here's the quick run-down of everything you need to know.

1. Can I re-fill the Sustee?

Yes, refills are available and should only be required from approx. 6-9 months pending the quality of your soil mix.

2. Is the device recyclable?

Oh yes, Sustee is recyclable and reusable (even better)

3. Can I use for any plants, outside pots too?

Yep! It sure can. It can be used for almost all plants that grow in soils with a certain level of moisture retention: from bog moss to gardening culture soil, Akadama soil, black earth, bark, coco peat, pet moss and vermiculite. 

4. How does it all work? 

Sustee senses water at the root level. It stays in your pot to continuously monitor your soil humidity and tells you when to top up, or if the soil is hydrated enough already. Sustee helps prevent withering and root rot - keeping your houseplants healthy so they can purify the air.

5. What size do I buy?

Sustee size S is best for small or shallow pots with plant roots about 2 inches deep
Sustee size M is best for pots 4.7 to 8 inches in diameter 
Sustee size L is best for pots more than 8 inches in diameter
Shop each size here.

6. Can I take it out and move it to another pot?

Yup, just make sure you let your Sustee dry for 24hrs then place into the new potted plant. The Sustee needs time to dry out completely before going back to white.

7. Where should I insert it in the pot?

It is important for Sustee to measure the moisture area around the roots. So please insert within 20 centimetres from the plant.

8. How do I know when to water?

Please give me water when the small window on the top of the Sustee becomes white - if it is blue it's hydrated so you only water me once I turn back to white. Yep it's that easy and you will be surprised how little or how much your plant really requires.

sustee watering checker the offical store

9. What if my Sustee arrives and my indoor plants are already watered?

Simply prime your new Sustee by placing into a cup of water and wait till the window turns blue then place into your already watered plant.

10. What kind of plants can you use Sustee on?

It can be used for almost all plants cultivated in soil or potting mixes. It can also be used in spaces like vegetable cultivation using a planter or pot.

11. What do I do when watering does not change the Sustee's colour?

The water absorption is probably hindered by something.

"It did not change colour as soon as I watered" 
It may be because the amount of water was too little. After inserting the Sustee, give your plant a good soak until the water flows out to the bottom of the pot. 

"Moisture is not being absorbed by the Sustee" 
Sustee absorbs moisture from the mouthpiece at the bottom. If it gets clogged with old hardened soil or there are excessive roots in the pot, the water may not be absorbed and colour change may not be possible. You can fix this by

    1. Loosening the soil a little when inserting the Sustee or changing the place to insert.
    2. Mix detergent with warm water and place SUSTEE window end down and let it soak for about an hour. Whatever is sticking to Sustee will be cleaned off. Dry and then use again.

12. How long does Sustee take to change colour?

  • Sustee size Small is about 3 minutes,
  • Medium size is about 10 minutes,
  • Large size is about 25 minutes for full-colour change in the window.

Depending on the soil, the colour may change after 1 hour. The quickness of colour change also depends on the water retention of the soil. Please refer time as a guide only and remember to water generously when using Sustee for the first time.

13. How to tell if you need to replace the Sustee core?

"It showed no reaction at all even when I watered it." If you continue to use for a long time, the reaction of colour change may become dull due to the deposition of the components and particulates in the soil. Replacement of the core is recommended in this case. 
*If you have a malfunction at the initial use of Sustee please feel free to contact us for advice or a replacement.

14. How deep can you insert it?

  • Please insert it until the "Ω" mark printed on the product is hidden. 
  • If you insert it shallower than the "Ω" mark, it may degrade the accuracy of the colour change.


15. Do you recommend keeping it blue?

We recommend that you do not water when the window is blue, only water when it turns white. You may feel like wanting add water in the middle of the colour change but you don't want to over-water your plant friends!

16. What does each colour mean?

When it is blue, it means that the soil which does not need watering and is moist. When it's white it means that the soil is dry and needs some watering.

17. Does the frequency of colour change, change with the season? 

In the hot summer season, the moisture in your pot evaporates quickly, so it will turn white quicker compared to the spring and autumn months. Opposite to this, It is difficult to evaporate the moisture during the cold winter season, so the blue period tends to be longer.

18. Does the use of inorganic fertilizer, organic fertilizer, pesticide, etc. affect the product?

Unless used in excess or if the product contains a lot of oil, it should not affect the Sustee.

Sustee the award winning houseplant watering device - watering tricks

 19. What do I need to do to care for my Sustee?

After long periods of usage Sustee might not react as swiftly as it should. This may be due to soil sticking to it. Mix neutral detergent with warm water and place upside down (the window facing downwards) in it and let it soak for about an hour. Whatever is sticking to Sustee should come off and dissolve this way. 

After cleaning let dry till it shows white. It can be used again after cleaning.

20. How much water should I use?

The correct amount of water is equal to a fifth to a quarter of whatever volume your pot holds. Try to water evenly.

21. So can I show it off to all my friends?

Sure you can, it's the only watering device in Australia! Why wouldn't you want to help out another struggling plant parent? don't forget to tag us @plantsinabox and #sustee.

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