Fleece Flower

Fleece Flower is a name that may strike terror into the heart of anyone who has had a run-in with Japanese Knotweed. I've struggled with Knotweed myself and can tell you firsthand that it is a horribly invasive plant that is next to impossible to irradiate. 

Fleece Flower, Persicaria polymorpha and Knotweed look very similar, so the confusion with these two plants is understandable. But unlike Knotweed, Persicaria polymorpha does not spread or self-seed. It's a clump-forming perennial that has been well-behaved in my garden for at least a decade.

Fleece Flower in my garden.

Giant Fleece Flower (on the middle right) mixing in with other late-season perennials 

at Grange Hollow Nursery.

Though it has the proportions of a large shrub, Fleece Flower is a herbaceous perennial that dies right back to the ground in fall. New growth rockets upward each spring, and by the end of June, it's almost six feet tall. In July it is covered in big white plumes. As they age, the flowers take on an attractive pinkish hue (see picture above). The flowers do have one minor flaw. Their fragrance is acidic and a bit unpleasant (in my humble opinion).

My Persicaria polymorpha is in a somewhat sheltered spot against a fence, but the plant's stems are so sturdy I don't imagine you'd have to stake them even in a more open location. My plant gets morning sun/afternoon shade, but I have seen them planted in full sun.

Fleece Flowers are pretty adaptable to a range of soils. I have never had to water my plant, even during a drought, so I'd say it's pretty adaptable to a range of moisture conditions as well. 

Japanese Beetles seem to the only pests. They haven't been a huge nuisance, but they do like the flowers. 

Plant type: Perennial

Height: 3-6 ft

Spread: 3-5 ft

Flower: White

Bloom period: Summer

Leaf: Green, lance-shaped leaf

Light: Sun to part-shade

Companion Plants: Ornamental grasses, Echinacea, Rudbeckia

Divide: Spring or fall

Problems: Japanese Beetles

USDA Zones: 4-9

 Persicaria microcephala 'Red Dragon' at the Niagara Botanical Garden 

Fleece Flower, Persicaria microcephala can be a problem plant. The species plant is native to China where it can be found in moist grasslands and forested areas.  It spreads by stolon or runners which are stems that grow at the surface or just below the ground.

Persicaria microcephala 'Red Dragon' is a sterile cultivar that is clump-forming. The reason to grow this perennial is the interesting lance-shaped foliage with its lipstick-red stems. The leaves are purplish-brown with a blue-green chevron in the spring. By summer the leaves are silvery-purple and become greener in the fall (in hotter climates the leaf color change may not be as dramatic).

'Red Dragon' has small white flowers from September to October.  Like Giant Fleece Flower it is tolerant of a number of soil types including clay. 'Red Dragon' prefers somewhat moist conditions, so water it well especially in its first year.

I have tried to overwinter this plant without success. In colder climates, like mine, you may need to grow this as an annual or overwinter it in a protected spot.

Plant type: Perennial

Height: 23-35 inches (60-90 cm)

Spread: 23-35 inches (60-90 cm)

Flower: Tiny white flowers

Bloom period: Summer

Leaf: Lance-shaped, green, silver and bronze leaf

Light: Sun to part-shade

Divide: Spring or fall

Problems: No serious problems

USDA Zones: 5-8

A really short Youtube video that may give you the best idea 

of the size and shape of 'Red Dragon'