Ladybird
Coccinella septempunctata
Role in the garden
A predator of aphids and scale insects. According to Hodek & Honěk (Ecology of Coccinellidae, 1996), an adult consumes 20 to 60 aphids a day; the larvae, more voracious, can consume several hundred over their cycle. The popular figure of “200 aphids a day” is a generalisation.
Activity period
March to October (overwinters as an adult)
How to attract / manage it
Caution: the Asian ladybird (Harmonia axyridis), introduced for biological control then escaped, has become invasive in Europe and competes with our native ladybirds. To recognise it: 8-10 mm and very variable in colour; the two commonest forms are black with two red spots and orange with 18 black spots (RHS).
Practical guide
Where to find them
Near aphid colonies: nettle, nasturtium, broad bean. The larva is recognisable: elongated, dark grey with orange spots, 6 legs. The pupa is immobile, shaped like a black/orange teardrop stuck on a leaf.
Sources
- Hodek, I. & Honěk, A. (1996). Ecology of Coccinellidae. Dordrecht : Kluwer Academic Publishers.
- Roy, H.E. et al. (2016). The harlequin ladybird, Harmonia axyridis: global perspectives on invasion history and ecology. Biological Invasions, 18(4), 997-1044.
- RHS (Royal Horticultural Society) : Ladybirds (rhs.org.uk/biodiversity/ladybirds)
Favourite plants / resources
Related plant entries
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Yarrow
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