Self-Watering Planter with a Water Level Window

How self-watering works

A cotton cord lies on the bottom of the reservoir and goes through a hole in the bottom of the basket into the soil. Water rises along the cord on its own, and the plant takes as much as it evaporates. There are 8 mm of air between the water and the bottom of the basket, so the roots never sit in water and don’t rot.

You top up through a notch in the rim at the back without lifting the plant out. A shop-bought pot goes into the basket as it is — the cord goes into its drainage hole. You can also plant straight into the basket.

The water level window

A float with a pointer sits in the reservoir. When you add water the pointer rises and an orange bar grows in the window at the front. Next to it are “full”, “half” and “refill” marks: no need to peek inside to know when to water. The window sits above the highest water level, so nothing leaks through it.

How long the water lasts

• 9 cm — 265 ml reservoir, 9–19 days.
• 12 cm — 540 ml, 11–21 days.
• 14 cm — 807 ml, 12–23 days.
• “Wave” with a saucer — 3–6 days.

This is an estimate for a room with no drafts or direct sun. In summer or next to a radiator the plant drinks more, so count the days with a margin.

Limitations

• Pots of the same diameter come in different heights: the 12 cm basket takes a pot up to 112 mm tall. If yours is taller, tell us the height and we’ll print a basket to fit.
• The cotton cord rots over time — replace it every 6–12 months.
• If you feed the plant through the reservoir, flush the soil from the top and drain the water every 1–2 months so salts don’t build up.
• A hanging planter with wet soil weighs up to 2 kg: put the hook into concrete or a beam, not a suspended ceiling.
• The “Wave” wall is 0.8 mm: it’s an indoor planter, not for outdoors.