Dock beetle
A small metallic green beetle whose larvae strip sorrel and dock leaves down to a lace of veins, leaving the leaf outline intact with the tissue eaten away between them. That skeletonising is the identification and it is unlike anything else that eats a sorrel leaf: slugs remove the leaf edge and make holes through it, while these larvae graze the surface until only the framework is left.
Caused by: Gastrophysa viridula · also called green dock beetle, sorrel beetle
What brings it on
Wherever docks grow, which in practice means almost any garden with rough ground near it — sorrel is the same genus and is colonised from them. Several generations run through the summer, and the gravid females are conspicuous because the abdomen swells until it looks as though the beetle is inflated.
source
Sourced guidancemoderate confidence
- Royal Horticultural Society: Sorrel — pests
- Garden Organic — Garden Organic (Henry Doubleday Research Association): Dock beetle
Checked 2026-08-13
Usually seen: April, May, June, July, August
Preventing it
Ordered by how much difference each measure actually makes, not by how often it is repeated.
- Remove docks near the sorrel bed, which is where the beetles come from and breed, and pick sorrel young and often — a bed that is being cut regularly rarely holds enough leaf for a generation to build on.
source
Horticultural consensusmoderate confidence
- Garden Organic — Garden Organic (Henry Doubleday Research Association): Dock beetle
Checked 2026-08-13
Dealing with it once it is there
- Cut the whole clump to the ground and compost the skeletonised leaves. Sorrel is a vigorous perennial and reshoots within a fortnight, so a hard cut removes the larvae with the crop and produces the tender young leaves worth eating anyway.
source
Sourced guidancemoderate confidence
- Royal Horticultural Society: Sorrel — cultivation
Checked 2026-08-13
What it affects
On sprays and treatments
GrowingHQ does not tell anyone what to apply, at what rate, or how often. Pesticide approvals differ by country, change without notice, and the product label is legally binding — it is also the document you are holding. What is described here is cultural and physical control, which is what a home grower can act on without a label in front of them.