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Description

Eupatorium excels as a conventional perennial and is invaluable for the late-summer border. They flower fairly late in the season and are a good replacement plant, filling the space left by early flowering species. They are splendid companions for other late perennials such as Echinacea, Rudbeckia and Helenium or grasses.
The stems are strong and purposeful, you won't find this plant succumbing to strong winds, and are almost entirely purple. Flowers,
appearing from July and continuing until autumn, the plants are crowned with large, domed panicles of pinkish-purple nectar-rich flowers, made up of numerous small flowers, so rich in pollen and nectar that they provide a feast for butterflies, bees 
Sowing: Sow seed in cool weather in autumn or early spring.
Sow the seeds very finely onto the surface of trays or pots containing moist seed compost. Just cover with a sprinkling of sieved compost or vermiculite. Place in a plastic bag or cover pots or trays with perspex and place in a position to maintain an optimum temperature of 20°C (68°F)
Keep the compost moist but not saturated, water from the base of the container and drain thoroughly. Germination usually takes 21 to 40 days at 18 to 24°C (65 to 75°F). Remove the cover once the seedlings begin to germinate to allow air to circulation.