The lift test

Lift the pot: if it feels heavy, wait; if it feels surprisingly light, water. Water is heavy — a cup weighs about half a pound — so a pot loses a lot of weight as it dries. With two weigh-ins on a kitchen scale you can turn that feeling into a number you can trust.

This is the best method for pots where your finger can’t reach the roots: deep pots, plants with a top layer of pebbles, and anything you’ve repotted into chunky mix.

How to calibrate it (two days, two numbers)

1. Weigh it wet. Water thoroughly until water runs out of the hole, let it drain for 15 minutes, then put the whole pot on a kitchen scale. Write the number on a piece of tape on the pot.
2. Weigh it dry. When the soil is at the point where the plant needs water (top 2 inches dry for most tropicals, bone dry for succulents — see the watering chart), weigh again. Write that number too.
3. Your trigger is the dry number. Most leafy plants are ready for water when the pot has lost about half of the weight it gained when you watered.

A worked example

Here’s how the math works, with illustrative numbers for a 6-inch plastic pot. Your own pot will weigh something different — that’s why you weigh it.

Moment	Weight	What it means
Right after watering (drained)	1,450 g (3.2 lb)	Full
4 days later	1,250 g (2.75 lb)	Still moist — wait
7 days later	1,080 g (2.4 lb)	Top 2 inches dry — water now
If you forgot: 12 days later	950 g (2.1 lb)	Bone dry — water slowly or bottom-water

In this example the pot gains about 370 g (13 oz) when watered. Watering when it drops back to around 1,100 g keeps the roots moist without staying soggy.

Why it beats a schedule

• It adjusts by itself to heat waves, cloudy weeks and the heating season.
• It catches overwatering. If the pot is still heavy a week later, you know the soil isn’t drying — a warning sign for root rot. Overwatered or underwatered? →
• It’s fast. Lifting six pots takes less time than poking six fingers in soil.

Plants where the lift test shines

Plant	Lift test tip
Snake plant	Water only when the pot is at its lightest. Heavy = don’t touch.
ZZ plant	Same as snake plant; it can stay “light” for a week with no harm.
Monstera	Water at the halfway point; the big leaves drink fast in summer.
Fiddle leaf fig	Hates both extremes — weigh weekly to keep it steady.
Hanging baskets	Reach up and push from below; a light basket swings easily.

Limits

• Very large pots: tilt the pot a few degrees instead of lifting, or use a moisture meter.
• Self-watering pots: check the reservoir indicator instead.
• Fresh repot: new soil changes the weights. Recalibrate after repotting — here’s when and how to repot.

Prefer not to weigh anything? The watering calculator gives you check dates based on the plant, pot and light.