---
title: Needs and health: how the terrarium simulator works
description: Each day every living thing scores its needs; health follows the score. Eight needs are scored every day: light, soil water, air humidity, temperature, pH,...
url: https://glassjar.garden/guide/how-it-works/needs-and-health/
---

How it works

# Needs and health

Each day every living thing scores its needs; health follows the score.

- Eight needs are scored every day: light, soil water, air humidity, temperature, pH, soil type, food and room.
- Inside its comfortable range a need scores full marks; outside, the score falls smoothly with distance.
- The scores combine so the worst one counts most.
- Health drifts toward the combined score: fast for drought, heat and dry air, slowly for the rest.
- Low health slows growth and pales leaves. It never kills on its own.

## Stats

- Fast needs: health moves 10% of the gap a day

- Slow needs: 3% a day

- Weighting: soft minimum, power -4

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

[Death and hazards →](https://glassjar.garden/guide/how-it-works/death-and-hazards/)