Woodland Trust

Nature's CalendarNature Detectives

Have you spotted the first flowering of elder yet?

Holly blue wings closed. Bob Carterholly blue

Celastrina argiolus

  • Shining, sky blue upperside wings with fine borders
  • The female has heavy dark borders to its forewings

holly blue butterfly fact sheet

Holly blue. www.moorhen.me.ukWhere found

Bushy, wooded habitat, often in woodland clearings and margins where its larvae feed on many plants, eg holly, bramble, gorse and ivy.

Common in Southern England, Wales and parts of Northern Ireland.

When to look for

Holly blue. www.moorhen.me.ukFabulous holly blue facts

  • The holly blue emerges well before the other blue butterflies in spring

  • It flies high around bushes and trees, unlike other grassland blues which tend to stay near ground level

  • It is much the commonest blue found in parks and gardens, where it congregates around holly in spring and ivy in autumn

  • Caterpillars are usually green, but some may be camouflaged with pinky stripes

  • Adults drink oozing sap, aphid honeydew and carrion juices

  • In England, it often breeds in churchyards, many of which have holly and ivy

  • Early entomologists thought that male and female holly blue butterflies were of different species. Common names for the male included 'wood blue' or 'azure blue' and females were known as 'blue spekt butterfly with black tips'

  • Widespread in Europe, and can be found as far as Japan, North America and North Africa