Growing Astilbe in Canada
Feathery plumes for the shade, as long as the soil stays moist.
Growing astilbe in Canada is mostly about water. NC State describes hybrid astilbe as a shade-loving perennial that needs organically rich, well-drained but moist soil, and warns that in hot summers or drought the foliage declines if the soil dries.
It is hardy. NC State rates Astilbe x arendsii to US Zone 3, which makes it one of the toughest flowering perennials for shade.
Astilbe at a glance: Plant in dappled or partial shade in rich, moist, well-drained soil. Keep it watered through dry spells. Different varieties bloom from late spring to fall. Divide about every four years, in spring or fall. Rated to US Zone 3.
Planning a shade bed? See Growing Fuchsia in Canada for a shade basket to go with it.
Light and Soil
NC State: astilbe prefers shady, moist sites with organically rich, well-drained soil. It can grow in full sun only if the soil stays constantly moist. It suits shade gardens, woodland edges, wet spots and the banks of ponds and streams.
Water Through Summer
The same source says that in hot summers or periods of drought the foliage declines if the soil is not kept moist. A mulch and a deep watering in dry spells keep the leaves looking good through the season.
Bloom Times
NC State says varieties bloom from late spring, early summer, mid-summer, late summer or fall, depending on the cultivar. Plumes come in red, pink, peach, purple and white, and the dried seed heads stay ornamental into winter. Mixing early and late varieties stretches the show.
Dividing
NC State recommends dividing plants about every four years, preferably in spring or fall. It lists no serious pest or disease problems, and notes astilbe is resistant to rabbits and deer.
Hardiness
NC State rates hybrid astilbe to US Zone 3. US zones are built differently from Canadian zones; see USDA vs Canadian zones and the shade perennials by zone table.
Frequently Asked Questions
Does astilbe grow in shade?
Yes. NC State says it prefers shady, moist sites, and does best in dappled or partial shade.
Why are my astilbe leaves turning brown?
Usually dry soil. NC State says the foliage declines in hot summers or drought if the soil is not kept moist.
Can astilbe grow in full sun?
Only with constantly moist soil, according to NC State.
When does astilbe bloom?
From late spring to fall, depending on the variety.
How often should I divide astilbe?
About every four years, in spring or fall, according to NC State.
Is astilbe hardy in Canada?
NC State rates hybrid astilbe to US Zone 3, which makes it one of the hardiest flowering shade perennials.