---
title: Water: how the terrarium simulator works | Glass Jar Garden
description: Soil fills to what it can hold; the rest drains to the drainage layer. Layers go in damp, at about three quarters of what they hold. Gravel, LECA or lava...
url: https://glassjar.garden/guide/how-it-works/water/
---

How it works

# Water

Soil fills to what it can hold; the rest drains to the drainage layer.

- Layers go in damp, at about three quarters of what they hold.
- Gravel, LECA or lava rock under the soil catches excess water below the roots.
- Water wicks up from a wet drainage layer, and sideways into drier soil.
- When water rises into the root zone, roots start to rot.
- An as-needed watering tops the soil back up to 92% and no further.

## Stats

- Wilting point: 30% of capacity

- Root zone: 3.5 cm

- Wicking up peat or coir: 4.5 cm

- Sideways spread: 20% of the gap a day

[See it in a jar](https://glassjar.garden/?guide=how-it-works/water)

[← Soil](https://glassjar.garden/guide/how-it-works/soil/) · [Humidity and the lid →](https://glassjar.garden/guide/how-it-works/humidity-and-the-lid/)