Groundsel
Broadleaf annual weed
Groundsel is a familiar annual weed of bare soil and neglected corners, capable of flowering and seeding in almost any month. It is not showy, but its fluffy seed heads reveal how readily it spreads. Deal with it promptly, especially before buds open, to prevent repeated flushes around cultivated ground.
How to identify it
Groundsel usually grows upright, reaching 10 to 45 cm tall. Its pale to mid-green leaves are irregularly lobed, slightly toothed and clasp the stem at their bases. The stems may branch freely. Small cylindrical yellow flower heads are often edged with dark-tipped bracts and usually lack obvious ray petals. They become white, fluffy seed heads like miniature dandelion clocks. Roots are shallow and fibrous, so young plants lift easily. Crushed foliage can have a distinctive, sharp smell.
Where it grows
It is widespread in UK gardens, allotments, paving cracks, compost heaps and bare patches beside walls or sheds. Seeds germinate over a long season, particularly in cultivated or lightly disturbed soil. Mild weather allows it to flower through winter in sheltered places. It tolerates poor ground as well as fertile vegetable beds.
Why it is a problem
Groundsel can produce seed very quickly and several generations may grow in one year. Its windborne fluffy seeds travel into neighbouring beds and pots, making it a persistent source of new seedlings. In vegetable plots it competes with crops, while flowering plants soon give neglected areas an untidy, weedy appearance.
How to control it
Hoe seedlings in dry weather before buds form, then leave the uprooted plants where they can dry. Hand-pull larger plants from moist soil, removing the fibrous root system, and collect any with open flowers or fluffy seed heads. Mulch bare ground around established plants and use light-excluding covers on vacant plots. Check disturbed soil regularly because buried seed can germinate after digging. Persistence and timely removal prevent each new generation from seeding.
Commonly confused with
It can be mistaken for ragwort seedlings, which develop more deeply cut leaves and later larger yellow daisy flowers. Groundsel also resembles some sow-thistles at an early stage, but its small cylindrical flower heads and fluffy seeds on short stems distinguish it.
Groundsel: frequently asked questions
How do I identify groundsel?
Groundsel usually grows upright, reaching 10 to 45 cm tall.
How do I get rid of groundsel?
Hoe seedlings in dry weather before buds form, then leave the uprooted plants where they can dry.
Where does groundsel grow?
It is widespread in UK gardens, allotments, paving cracks, compost heaps and bare patches beside walls or sheds.
General guidance for UK gardens and allotments, focused on prevention and non-chemical control. For a confirmed identification, the RHS or a local garden centre can help. Page updated 19 Sep 2026.