Woodlice home for a short stay can be kept in a small container, say a plastic lunchbox or sandwich box. Longer residents need somewhere larger; an old fish tank or plastic box is fine.

Be aware that woodlice die just as easily from too much water as from too little; so, spray the container often to keep things moist, but not too often, or you will end up with a defunct colony.

The container should have anything from a thin layer (mine has 1/2″) to a few inches of potting soil, depending on the species; pill bugs like to burrow more than common rough woodlice, for example.

On top of this should be a few pieces of bark, oak seems to be the best, and some leaf litter; personally, I use leftover sphagnum moss from my other terrariums, and some old bits of houseplant; I use bits of old millet plant and ‘flaming katy’ stems, they seem to be fine.

Refresh the woodlice with grated carrot or bits of fruit when it runs out (carrot is best, I use apple as I have no carrot), this should keep them healthy.

In the same way that millipedes need calcium, woodlice need copper; hence the carrot, as it is a good source of copper.