Basic information about Astilbes. Includes Origin, Growing & Cultivation, Common Pests & Diseases, Interesting Facts & Uses, and Garden Design Tips.
Astilbe is native to Asia and North America.
Growing and Cultivation
Astilbe prefers partial shade (they can burn in full sun) and soil that drains well: they don’t tolerate soils prone to puddling in rain or getting water-logged. Amending your soil with peat moss, perlite or coarse sand is recommended for heavy soils. They do need consistent moisture (just not too much all at once). If it does not rain, they would like a moderate amount of water every week.
Astilbe enjoy a dose or 2 of fertilizer during the year (Phosphorus is especially appreciated), or a top-dressing of compost in the spring. They are also pleased with a 2 inch layer of moisture-retentive mulch (wood chips) around them (never on top of!).
The crown of Astilbe plants often lifts above the soil as they grow – you should sprinkle/cover them with soil (in spring before much foliage growth) or lift and replant them. Astilbe should be divided every 3 to 4 years as needed. This should be done in spring.
Common Pests and Diseases
While Astilbe is relatively pest and disease resistant, occasionally it can develop powdery mildew or bacterial leaf spots. The tarnished plant bug and groundhogs will sometimes snack on it. Astilbe is both rabbit and deer resistant – they prefer not to eat it.
Powdery Mildew is a fungus easily identified by the white/gray powdery substance sitting on leaves. It can be prevented by good air circulation, and treated if it appears with fungicidal sprays, horticultural oils, sulfur and/or sodium bicarbonate.
Some examples of powdery mildew:
Bacterial Leaf Spot
Bacterial Leaf Spot presents as brown or black water-soaked looking spots on leaves that grow in size. It is unfortunately not very treatable. Copper fungicides have shown some limited control capability, but bacterial leaf spot will not be eradicated. Bacterial leaf spot does not kill plants directly; only if it’s severely affected will bacterial leaf spot cause a decline in vigor of your plant. Some people may choose to just live with the minimal damage and discoloration. If this shows up, though, the only sure way to be rid of it is to remove the plant and plant something not susceptible in its place: that area in the garden is infected with the bacteria.
Some examples of bacterial leaf spot:
Tarnished plant bugs
Tarnished plant bugs can be picked off and drowned in water mixed with a few drops of dish soap (breaks water cohesion that some bugs use to float) or can be treated with an insecticide. They look like this:
Groundhogs are large furry burrowing rodents that can get up to 14 pounds! They eat a lot to support that bulk, and can decimate a garden. There are traps, poisons, and fumigation compounds you get use to get rid of them, as well as (possibly less effective) ‘scare tactics’ you can use to try to frighten them off.
Interesting Facts and Uses
The Astilbe plant’s feathery-textured floral plumes can be used for cut flowers, fresh or dried. Astilbe flowers attract butterflies and possibly hummingbirds, making it a good addition to a pollinator-friendly garden.
Garden Design Tips
Astilbe’s beautiful feathery plumes and delicate, ferny foliage add color and texture to perennial gardens. They can be used together with each other as contrasting varieties en masse, or to complement other plants with big or broad leaves, such as hosta, heuchera, irises, daylilies, ligularia, cimicifuga, etc. They are best displayed at the front of the mixed boarder or lining pathways.
To purchase Astilbe varieties, please visit our Buy Astilbe Page.
To learn about the differences between Astilbe species, please visit our Astilbe Species Information Page.