The simplest moisture meter is your finger. Push it into the potting mix, about two knuckles deep (roughly 5 cm). If it feels dry at that depth, most leafy houseplants are ready for water. If it feels cool and damp, wait and check again in a day or two. Cacti and succulents are the exception: they like to dry out much further before the next drink.
The second test is weight. Lift the pot just after a good watering and notice how heavy it feels. Lift it again a few days later. Dry mix is much lighter than wet mix, and after a few tries you can tell by feel, even for pots too deep to finger-test.
Wilting is a less reliable signal. A thirsty plant droops, but a plant whose roots are sitting in soggy mix can droop too, because damaged roots cannot take up water. If a plant is wilting and the mix is still wet, do not add more water. Probe-style water meters exist, but Illinois Extension notes they are not always reliable, so trust your finger first.
Key points
- Check about 5 cm down; water most leafy plants when it feels dry there.
- A dry pot feels noticeably lighter than a freshly watered one.
- Wilting with wet mix means too much water, not too little.
Try this
Water one plant thoroughly, lift it and note the weight. Lift it again each day this week until it feels light, then do the finger test to confirm.
Check yourself
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Sources
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