Often confused with non-native giant hogweed, common hogweed (Heracleum sphondylium) is a native biennial or short-lived perennial wildflower (often classed as a weed), found in hedgerows, roadside verges, allotments and waste ground. So-named as it was once used as pig fodder, it bears large, plate-like clusters of cream-white flowers from May to August, which attract a huge range of insects, particularly flies. It has hollow, hairy stems and large hairy, divided leaves. Its stems persist after the plant has finished flowering, and may be used by nesting solitary bees the following spring.

Like giant hogweed and similar looking cow parsley, it's a member of the carrot family (Apiaceae). Like giant hogweed, its sap is toxic, although far less so. While touching its sap won't cause burns as significant as those of giant hogweed, it's advisable to wear gloves when handling and wash hands after contact.

How to identify common hogweed

Common hogweed is a tall-growing plant, reaching heights of up to 2m. Its flowerheads can reach 20cm across and its rounded leaves can be up to 60cm in length. It has hairy, hollow, and grooved stems. It's often mistaken for giant hogweed, which can grow up to 5m in height and has more pointed leaves. It's also sometimes mistaken for cow parsley, which has more finely divided, filigree leaves.

Plant calendar

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Heracleum and wildlife

Heracleum is known for attracting bees and beneficial insects.

Is known to attract Bees
Bees
Is known to attract Beneficial insects
Beneficial insects
Is not known to attract Birds
Birds
Is not known to attract Butterflies/​Moths
Butterflies/​Moths
Is not known to attract Other pollinators
Other pollinators

Is Heracleum poisonous?

Heracleum irritates skin.

Toxic to:
Is known to attract People
People
No reported toxicity to:
Is not known to attract Birds
Birds
Is not known to attract Cats
Cats
Is not known to attract Dogs
Dogs
Is not known to attract Horses
Horses
Is not known to attract Livestock
Livestock
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