Beauty queen filipendula
Filipendula is a genus of hardy perennials known for airy clusters of tiny flowers held above deeply divided foliage. Depending on the species and cultivar, the flowers may be white, cream, pale pink or deep rose. There are species from around the globe but none native to Canada.
The best-known member is queen of the prairie, Filipendula rubra, which is native to North America but not Canada. It produces large, feathery pink flower heads on stems that can reach 6 to 8 feet tall. A mature plant may spread 3 to 4 feet wide, and several stems together can create a striking cloud of colour in early to midsummer.
Growing queen of the prairie
Queen of the prairie grows in full sun or partial shade. It prefers fertile soil that holds moisture, but it does not need to stand in wet ground.
An established plant may survive periods of drier soil, particularly in a mulched garden bed. Growth and flowering are likely to be reduced, however, and the leaves may develop brown, scorched edges if the soil becomes very dry. Regular garden watering during long rainless periods will usually be enough in soil that retains moisture reasonably well.
Full sun generally produces the strongest flowering and sturdier stems in cooler climates. Plants grown in considerable shade may lean and produce fewer flowers.
A plant that needs space
Queen of the prairie spreads through underground rhizomes and can gradually form a broad colony. This makes it well suited to the back of a large perennial border, a naturalistic planting or an area where several stems can be allowed to develop together.
In a small bed, its spread may need to be controlled by removing unwanted shoots or dividing the clump in spring. It is generally easy to grow once established and has few serious pest problems.
The cultivar ‘Venusta’ is one of the most commonly grown forms of Filipendula rubra. It produces rich pink flowers and usually grows about 5 to 8 feet tall.
Other filipendula
Several other filipendula species and cultivars are grown in gardens. Meadowsweet, Filipendula ulmaria, is a Eurasian species with fragrant, creamy white flowers on plants generally 3 to 6 feet tall and hardy to Zone 3. It has shown a tendency to grow beyond the confines of cultivation in the Eastern provinces, so if you do choose to plant it in Ontario and eastward, keep it far from waterways.
Dropwort, Filipendula vulgaris, is another Eurasian species, growing about 2 to 3 feet tall above low, fern-like foliage. It is also hardy to about Zone 3, although the species and its double-flowered cultivars are usually found only through specialty perennial nurseries.
Japanese meadowsweet, Filipendula purpurea, produces pink to reddish flowers and is generally more compact. The commonly grown cultivar ‘Elegans’ reaches about 18 to 24 inches and is hardy to about Zone 3. It is the hardest of the three to find.
Planting and care
Plant filipendula in spring or early autumn and water it regularly during its first growing season. Compost can be added to improve the soil, and a layer of mulch will help retain moisture.
The old stems can be cut down after flowering or left standing until spring. Plants can be divided when the clump becomes too large or when additional plants are wanted.
If you have enough room and reasonably moisture-retentive soil, queen of the prairie is a dependable, long-lived perennial that provides height, texture and one of the most distinctive pink flower displays in the summer garden.
