Currant blister aphids

The the new leaves have recently unfurled on a redcurrant I bought over the winter. And the leaves have bright red blisters.

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Discoloured blistering on a young redcurrant leaf

These blisters look like a text book image for currant blister aphids. Sure enough, when I looked at the underside of the leaf, there was a big fat aphid with a brood of babies…

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Redcurrant leaf with blistering and aphids

These bugs must have come in as eggs on the plant. According to the RHS, the aphids need to move to hedge woundwort (Stachys sylvatica) plants to complete their life cycle: they’re uncommon plants around here, so this could be the end of the road for these aphids, depending how far they can travel. The damage the aphids are doing looks impressive, but is really of no consequence.