Ragwort - St. James Wort (Jacobaea vulgaris syn. senecio jacobaea) Wildflowers Flower
Height 6 ft 7 in
Stunning plant; over a season, plants can produce 2,000 to 2,500 yellow daisy like flowers in 20 to 60 headed, flat-topped corymbs (a flower cluster whose lower stalks are proportionally longer so that the flowers form a flat or slightly convex head) making them perfect for landing on.
Ragwort is generally considered to be biennial but has the tendency to be perennial. The stems are erect, straight, have no or few hairs. The leaves are pinnately lobed and the end lobe is blunted. The flower heads are hermaphrodite and are 1.5 to 2.5 centimetres (0.6 to 0.9 in) diameter, and are borne in dense, flat-topped clusters; the florets are bright yellow. It has a long flowering period lasting from June to November; dandelion like hairs help seed dispersal by wind. Most seeds do not travel a great distance from the parent plant and is easily controlled.
Ragwort aka Stinking Willie, is known by many names...St. James-wort, common ragwort, benweed, mare’s fart, tansy ragwort, ragweed, stinking willie, stinking nanny, dog standard, staggerwort, stammerwort, golden senecio and cankerwort. The many names that include the word 'stinking' (and Mare's Fart) stem from the fact that the leaves have an unpleasant smell - highly intoxicating to pollinators like bees, flies, butterflies and one moth in particular...the Cinnabar Moth.
Cinnabar Moths are important pollinators. The staple diet of the cinnabar moth caterpillar is ragwort. Ragwort is poisonous to livestock, however the caterpillars absorb the toxins into their bodies, giving them the foul taste that serves as their defence against predation. Their bold stripes look amazing to us, but these colours serve as a warning to predators that they are poisonous and not good to eat. The Cinnabar Moth is a pollinator of many nectar-rich plants, so they are highly beneficial to the environment.
Cinnabar moth caterpillars have distinctive black and orange bodies; they hatch from late June and are easy to spot as they make no attempt to stay out of sight relying instead on their foul taste to deter would-be predators. Whilst not currently uncommon their numbers are in decline, a situation that is worsened due to the control of ragwort that is currently taking place in the UK. We offer it here as it is essential for the Cinnabar moth to survive.
- Full sun
- poor soil; soil should be well draining.
- If starting indoors, the seeds will take about 2 to 3 weeks to germinate at 18 to 22 degrees centigrade and should be grown in the light and watered from below, as Ragwort are easily damaged by water.
- transplant outdoors after all risk of frost has passed
- remove seeds to control spread though not generally noted as leaving far from parent plant; keep seeds for future use or plant where desired
- great as border plant or stand alone feature plant
- leaves can be used to produce a green dye, the flowers, a yellow dye.
- Seed count: 1/2 gr