---
title: Common pill bug in a terrarium | Glass Jar Garden
description: Common pill bug (Armadillidium vulgare): The classic pill bug that rolls into a ball. Hardy and a steady breeder. Needs eats litter 1.5 mg/day each, eats...
url: https://glassjar.garden/guide/critters/armadillidium-vulgare/
---

Critters

# Common pill bug
Armadillidium vulgare

Fine in a closed jar · Grazes plants

The classic pill bug that rolls into a ball. Hardy and a steady breeder.

## What the simulation uses

- Eats litter: 1.5 mg/day each (Dead leaves one animal shreds a day, turning them back into soil.)

- Eats mould: 0.2 mg/day each (Mould one animal grazes a day, keeping fuzz and grey mould down.)

- Colony at most: 400 per m² (How many the floor can feed when food is plentiful; less food, fewer.)

- Starving loses: 2 % a day (How fast a colony thins when the jar cannot feed it.)

- Eats: decaying plant, leaf litter, fungi, animal waste, dead animals, seeds, seedlings (Foods it lives on; the jar feeds it from whichever of these it has.)

- Humidity: 60 to 90 % RH (Air moisture it needs.)

- Temperature: 10 to 27 °C (Comfortable range; beyond it the colony suffers.)

- Doubles in: 90 days (Time for the colony to double with plenty of food.)

- Lives: 730 days (How long one animal lives.)

## Care

- Size: 8.5 to 18 mm

- Moisture: Moist

## What kills it

- desiccation (main survival limit)
- flooding
- sustained heat above ~30 C
- freezing below 0 C induces dormancy

## Description
Each brood can bring up to 40 young, with up to three broods a season. Adults reach 1 to 2 cm and live up to three years. Keep the soil from drying out, and watch tender seedlings, which this group likes to nibble.

Also called pill bug, roly-poly, common pill woodlouse.

Estimated, where sources were thin: temp_c optimum; humidity_rh_pct; generation_days; population_doubling_days; clutch min.

## Sources

- [en.wikipedia.org/wiki/Armadillidium_vulgare](https://en.wikipedia.org/wiki/Armadillidium_vulgare)
- [en.wikipedia.org/wiki/Woodlouse](https://en.wikipedia.org/wiki/Woodlouse)
- [rhs.org.uk/biodiversity/woodlice](https://www.rhs.org.uk/biodiversity/woodlice)

[Grow it in a jar](https://glassjar.garden/?guide=critters/armadillidium-vulgare)

[Common rough woodlouse](https://glassjar.garden/guide/critters/porcellio-scaber/) · [All critters](https://glassjar.garden/guide/critters/)