Jelly Bean Isopods (Armadillidium vulgare 'St Lucia')

The Jelly Bean is the humble pillbug gone technicolour. Underneath the colour it is the ordinary common pill woodlouse, Armadillidium vulgare, the same hardy animal you might turn up under a log in the garden. What sets this one apart is where it comes from: a locality on the Caribbean island of St Lucia that throws a whole bag of colours in a single colony. Line a few up and they really do look like a scattered handful of multicoloured jelly bean sweets, which is how the 'Jelly Bean' name stuck.

The thing to understand is that this is a colour-variable locality, not a fixed single morph. One colony will show deep oranges and burgundies, soft yellows, greys and whites, calico patchworks and most shades in between, and no two animals look quite the same. People have tried to pin the colours down by pairing like with like, but the broods keep throwing the full range regardless of what the parents looked like. You cannot isolate a clean single-colour line from them, and that unpredictability is the whole appeal. Every generation hands you a fresh mix.

If you have kept other Armadillidium you will find these comfortably familiar. Where our Magic Potion is a selectively bred designer look and Zebra gives you crisp black-and-white striping, the Jelly Bean is all about natural variety in one tub. They sit alongside hardy favourites like granulatum and Gestroi, and you can see how the whole group compares in our Armadillidium collection. For a first pillbug, or a colourful addition to a shelf of them, they are hard to beat.

Care is straightforward common-pillbug care, which is a big part of why I point beginners towards them. Like every true pill woodlouse they conglobate, rolling into a tight sealed ball when startled, and being a vulgare they want a moisture gradient rather than a wet box. I keep mine at roughly 50 to 70 percent, with one damp corner and the rest left drier, and give them medium ventilation so the air stays fresh without drying everything out. Ordinary room temperature suits them all year, and they are about as hardy and forgiving as isopods get.

For the substrate I build a living base of flake soil, rotted hardwood and organic topsoil rather than a plain coco-coir bottom, which gives the microfauna something to work with and the isopods plenty to graze on. A generous top layer of leaf litter earns its keep as both food and cover, and our magnolia leaf litter holds its shape for months. Keep calcium available throughout, as a cuttlebone or crushed shell, because a colony this prolific is always moulting and needs it to harden fresh shells.

They are unfussy detritivores that take rotting wood and leaf litter as the backbone of the diet, topped up with the odd vegetable and a regular pinch of protein. They are also bolder than most isopods, often out in daylight and quick to a feed rather than hiding it away, which makes them a real pleasure to watch. Given a little warmth, steady calcium and room to grow, a small starter group builds into a busy colony surprisingly fast, and every brood keeps the colours coming.

Every order is captive-bred, boxed double-walled around a ventilated tub of damp sphagnum and posted Monday to Thursday by tracked next-day Royal Mail, with a live-arrival guarantee and a 20% overcount as standard.