Eutrochium maculatum ‘Riesenschirm’ AGM

Joe Pye Weed Asteraceae

If you want a plant with presence, ‘Riesenschirm’ has clearly never heard of understatement. This magnificent selection forms a towering clump of strong, dark purple-burgundy stems carrying whorls of toothed, dark green leaves, topped in late summer by enormous, domed heads of rich pink-purple flowers. The effect is part prairie giant, part floral thundercloud—and wonderfully useful at the back of a border. 

The species Eutrochium maculatum is native to eastern and central North America, occurring in moist meadows, woodland margins and wet ground. ‘Riesenschirm’ is particularly valuable where soil remains moist, although it will tolerate ordinary fertile garden soil provided it does not become excessively dry.

The name requires a little housekeeping. Kew and the RHS now favour Eutrochium maculatum, with Eupatorium maculatum treated as a synonym; the RHS places ‘Riesenschirm’ in the Atropurpureum Group.  The cultivar has an RHS Award of Garden Merit and is exceptionally hardy. 

Pollinator appeal: The broad flowerheads are superb late-season landing platforms, packed with tiny nectar- and pollen-rich disc florets. Eutrochium maculatum attracts a particularly wide range of insects, including bumblebees, honeybees, solitary bees, hoverflies, bee-flies, butterflies and skippers, with red admirals and peacocks among the larger visitors. The RHS’s pollinator trials found it particularly good for bumblebees and hoverflies. 

Height: 1.5–2.5m
Spread: 0.5–1m
Flowering: July–September
Hardiness: H7, below −20°C
Aspect: Sun or partial shade
Soil: Moist, fertile and preferably moisture-retentive