Compare the same container over time
Pot weight can help reveal a change from recently watered to substantially drier medium. Learn the difference on the same plant and container rather than comparing unrelated pots made from different materials.
Use weight alongside the plant's identity, activity and root-zone moisture. A heavy ceramic vessel can conceal small changes, while dry top dressing may mislead the eye. Record observations for a few cycles before deciding the clue is reliable for your setup.
FAQ
Can weight alone tell me exactly when to water?
No. It is a practical comparison, not a universal measurement of root health or seasonal needs.
Source
RHS: Growing houseplant cacti and succulents
Related plant reading
Succulent Growing Conditions: Identity Before Climate Claims