Smooth Aster
Symphyotrichum laeve
Smooth Aster (Symphyotrichum laeve) is a Colorado-native perennial suited to the Colorado Front Range. It matures to about 24–36 in tall and 18–24 in wide, needs low to medium water, and prefers full sun to partial shade. Smooth blue-green foliage; clouds of lavender daisies in fall; essential late-pollinator nectar.
Colorado nativeOn the CSU listlow to medium water24–36 in tall and 18–24 in wideXeric / water-wiseZones 1–3 (can be planted near the house)Deer-resistant
Photos
- Photo 1: Kathleen Houlahan Chayer, Wikimedia Commons (CC0)
- Photo 2: Shaun Pogacnik, Wikimedia Commons (CC0)
- Photo 3: Judy Gallagher, Wikimedia Commons (CC-BY)
At a glance
Will it survive here?
- Hardiness zones
- USDA 3–8
- Water needs
- low to medium water
- Sun
- Best in full sun; tolerates partial shade.
- Soil
- clay, loam, sandy
- Soil pH
- 6.5–8.0
- Hail tolerance
- high
- Wind tolerance
- high
- Salt tolerance
- moderate
- Firewise (defensible space)
- Zones 1–3 (can be planted near the house)
- Site uses
- Slopes & erosion control
How big, what shape?
- Mature size
- 24–36 in tall and 18–24 in wide
- Planting spacing
- ~17–24 in apart
What it looks like, and when
- Bloom time
- late summer, early fall
- Bloom color
- blue, purple
- Bloom length
- Long (several weeks)
- Foliage
- Deciduous
Who else benefits
- Pollinator value
- high
- Deer
- Generally deer-resistant
- Colorado native
- Yes
- Native ecoregion
- shortgrass prairie, foothills
Planting & establishment
Deep-water first season to establish, then minimal water needed.
Frequently asked questions
- Is Smooth Aster good for the Colorado Front Range?
- Yes, Smooth Aster is a well-suited perennial for Colorado's Front Range.
- How big does Smooth Aster get?
- It matures to about 24–36 in tall and 18–24 in wide.
- How far apart do I plant Smooth Aster?
- Space Smooth Aster about 17 in apart for a faster, fuller bed, or up to 24 in apart for a looser planting.
- Is Smooth Aster hardy on the Front Range?
- Smooth Aster is hardy in USDA 3–8. The Colorado Front Range spans roughly USDA 4b–6a, so it is well within range.
- How much water does Smooth Aster need?
- It needs low to medium water once established.
- Is Smooth Aster native to Colorado?
- Yes. It is a Colorado native.
- Is Smooth Aster deer-resistant?
- Smooth Aster is generally considered deer-resistant, though no plant is deer-proof when browse pressure is high.
- Is Smooth Aster a good firewise plant near the house?
- Smooth Aster is a lower-fuel choice suitable in defensible-space zones 1–3, it can be planted near the house when kept well irrigated and maintained. This is general suitability guidance based on CSU Extension firewise plant lists, not a guarantee that any plant won't burn, a well-irrigated, well-maintained plant is the goal. Follow CSU Extension defensible-space guidance and check with your local fire district before planting in the wildland-urban interface.
- How long does Smooth Aster bloom?
- Smooth Aster blooms for several weeks, a long-season performer on the Front Range. Bloom timing shifts a week or two with elevation and spring weather.
