Pictorial guide to the flora of the British Isles

Home ⟩ Pictorial Guide ⟩ Gentianaceae ⟩ Blackstonia perfoliata / yellow-wort

Blackstonia perfoliata (L.) Huds.

yellow-wort (Gentianaceae)

 SpreadBias within British IslesDirection of bias
WidespreadModerate tendencyS
Plant Atlas 2020
BSBI Distribution Map

With its paired leaves fused around the stem and yellow 8-petalled flowers, Blackstonia perfoliata is unmistakable.

Beaumaris (VC52: Anglesey); 2007-07-24

 yellow-wort / Blackstonia perfoliata: With its paired leaves fused around the stem and yellow 8-petalled flowers, _Blackstonia perfoliata_ is unmistakable.

The sepals of Blackstonia perfoliata are narrow and spiral round each other before the flower opens.

Aston Rowant (VC23: Oxfordshire); 2014-10-27

 yellow-wort / Blackstonia perfoliata: The sepals of _Blackstonia perfoliata_ are narrow and spiral round each other before the flower opens.

Blackstonia perfoliata is a primarily Mediterranean species found across England, Wales and the Republic of Ireland, mostly in calcareous areas.

Luton (VC30: Bedfordshire); 2009-06-11

 yellow-wort / Blackstonia perfoliata: _Blackstonia perfoliata_ is a primarily Mediterranean species found across England, Wales and the Republic of Ireland, mostly in calcareous areas.

The fruit of Blackstonia perfoliata is a pale, rounded capsule that opens up between the 2 valves.

Hawling (VC33: East Gloucestershire); 2021-11-14

 yellow-wort / Blackstonia perfoliata: The fruit of _Blackstonia perfoliata_ is a pale, rounded capsule that opens up between the 2 valves.

All images copyright © Christopher J. Dixon unless otherwise indicated.

L-R: Bidens tripartita, Melilotus officinalis, Mimulus guttatus, Thalictrum flavum, Ranunculus peltatus, Anchusa arvensis, Malva alcea, Lolium perenne