Sonchus bornmuelleri, or Bornmueller's sow-thistle, is a plant endemic to the Canary Island of La Palma.
Perennial with woody stock. Leaves in a basal rosette, pinnatifid with rounded lobes; margins subspinose. Scape up to 80 cm, with a few small bracts. Inflorescence a dense corymb of up to 20 heads. Heads densely tomentose.
Cliffs south of Santa Cruz de La Palma, coastal rocks near San Andrés y Los Sauces, lots pedregale (between the lighthouse and piscinas fajanas), Riscos de Bajamar, Garafia, Montaña del Viento, Mazo, Fuencaliente, etc., up to 200 m, rare.