Arkansas bluestar
Amsonia hubrichtii · Apocynaceae
Thread-fine leaves make a billowing, feathery mound that turns brilliant gold in autumn. Pale blue starry flowers open in late spring.
- Size
- 3 ft tall, 3 ft wide
- Zones
- 5 to 8
- Light
- Full sun to part sun
- Flowers
- Mid May to early June
- Pets
- No toxicity recorded
- Job in a bed
- Specimen
A bed built around Arkansas bluestar
The planner designed this bed around Arkansas bluestar when this page was made: a 12 × 6 ft (3.7 × 1.8 m) naturalistic planting in zone 6, full sun. It chose the other plants from the 966 that suit those conditions, and says below why Arkansas bluestar stands where it does.
The plants
- 1 Arkansas bluestar × 1, blue
- 2 Striped bloody cranesbill × 7, pink
- 3 Blue fescue × 8, blue-green leaves
- 4 Sneezeweed × 3, yellow
- 5 Gray's sedge × 3, green
- 6 Schubert's allium × 4, pink
- 7 Red spider lily × 12, red
Why this plant
- The only dense clusters. The others are open bowls, daisies, globes and others. Shape reads at a distance, where colours blur.
- The only blue.
Why here
- Anchors a back corner. At 3 ft it is one of the taller plants here, and the tallest close the ends of the bed, where they stand in front of nothing.
- A step in the back row. Next to Gray's sedge (2½ ft): no two neighbours there are the same height, so the back steps up and down like a skyline.
- One plant, alone. A feature plant is seen as an object, and needs clear ground around it.
Why now
- In flower for four weeks. From mid May to early June.
- Opens the season. In its first week nothing else on the plan is in flower.
Planned as a naturalistic planting: low grasses and groundcovers, the matrix, make up 58% of the planted ground. The most in flower at one time is 4 kinds, from late May. Arkansas bluestar and sneezeweed anchor the back corners of the bed: the tallest plants on the plan stand there.
The planner's own design check: 9 Excellent, 8 Good. It flags one thing to watch: Nothing on this plan is highly poisonous or an aggressive spreader.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where Arkansas bluestar goes in a border
At 3 ft it belongs in the middle of a bed. In the planner's ten height classes it is medium tall (2½ to 3 ft).
Its job: specimen. A feature plant with a shape of its own. It stands alone with room around it, and repeats only at a distance.
Grown for texture: the feathery foliage is the finest of any large perennial, and its gold in October is as good as any shrub's. Set it beside something bold, such as sedum 'Autumn Joy' or coneflower seed heads.
- Fine texture and gold autumn colour
- Massed as a low hedge of foliage
- A foil for bold leaves and seed heads
What to plant with Arkansas bluestar
Plants recorded as good partners for it, and what each pairing does:
- Sedum 'Autumn Joy': carries the spot on into mid October; bold leaves against its fine ones.
- Purple coneflower: takes over when it finishes, flowering from late June.
- Switchgrass 'Shenandoah': its green leaves are a setting for the flowers, before and after.
Questions about Arkansas bluestar
Does Arkansas bluestar need sun or shade?
Arkansas bluestar grows in full sun (6 or more hours of direct sun a day) and part sun (4 to 6 hours of sun, including some afternoon sun).
It wants ordinary well-drained soil, of average fertility, and a good soak in dry spells.
What zones does Arkansas bluestar grow in?
USDA zones 5 to 8. It is hardy to zone 5, which means it survives winter nights down to about −10 °F (−23 °C).
Above zone 8 it struggles: the zones measure winter cold, but a plant's top zone usually means the summers are too hot or the winters too mild for it to rest.
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does Arkansas bluestar flower in my zone?
In zone 5 it flowers mid May to early June. As a spring flower it moves about a week for every zone: earlier where it is warmer, later where it is colder.
| Zone 5 | Mid May to early June |
|---|---|
| Zone 6 | Early May to early June |
| Zone 7 | Early May to late May |
| Zone 8 | Late April to late May |
Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.
How far apart should Arkansas bluestar be planted?
2½ ft (75 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 3 ft (90 cm), so a group knits into one patch.
It grows 3 ft (90 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many Arkansas bluestar plants do I need?
At 2½ ft apart, set out in staggered rows:
- 2 to fill 10 square feet (about 1 m²)
- 5 for a single row 10 ft (3 m) long
- 6 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as one, with clear ground around it: a feature plant is seen as an object, and a group of them is a thicket.
In the bed above, the planner used one in one group.
Is Arkansas bluestar poisonous to dogs and cats?
No toxicity is recorded for dogs, cats, horses or people, according to NC State Extension. Not considered poisonous, but the milky sap can irritate sensitive skin.
"Not toxic" is not "edible": a pet that eats a lot of any plant can be sick.
Do deer eat Arkansas bluestar?
Mostly not. NC State lists it as resistant to deer. No plant is proof against a hungry deer in a hard winter, but this one is low on the menu.
What flowers after Arkansas bluestar?
Arkansas bluestar is over by early June. These start as it finishes and carry the same spot on, so it never goes flat:
- Purple coneflower: from late June to early September, 3 ft tall (a recorded partner).
- Butterfly weed: from late June to early August, 24 in tall, to stand in front of it and cover its fading stems.
- Daylily: from late June to early August, 2½ ft tall.
What does Arkansas bluestar look like in winter?
Arkansas bluestar dies down to the ground and there is nothing to see until spring. The old stems can be cut in autumn, or left until spring as shelter for overwintering insects.
Is Arkansas bluestar good for bees and butterflies?
Arkansas bluestar is visited by butterflies.
It is native to the United States.
More Amsonia
- Bluestar Amsonia tabernaemontana
- Bluestar 'Blue Ice' Amsonia 'Blue Ice'
- Bluestar 'Storm Cloud' Amsonia tabernaemontana 'Storm Cloud'
In these guides
- Deer-resistant perennials for full sun
- Pet-safe plants for a sunny border
- Native perennials for pollinators
- Plants for butterflies
- Plants with blue flowers
Every fact on record
- Type
- Perennial
- Size
- 3 ft (90 cm) tall, 3 ft (90 cm) wide
- Plant
- 2½ ft (75 cm) apart
- Height class
- Medium tall (2½ to 3 ft)
- Place in the bed
- Middle
- Flowers
- Mid May to early June; dense clusters; blue
- Leaves
- Fine texture, herbaceous; green
- Shape
- Mounding, clumping
- Hardy in
- USDA zones 5 to 8
- Light
- Full sun, part sun
- Soil
- Average, well-drained
- Water
- Moderate
- Feeding
- Light, in spring
- Family
- Apocynaceae
- Comes from
- Arkansas to Oklahoma
- Attracts
- Butterflies
- Stands up to
- Deer
Checked against NC State Extension. Flowering times are for zone 5: later in colder zones, earlier in warmer ones. Toxicity and spread information is a general gardening guide, not veterinary or medical advice, and invasive status varies by region. If a person or pet eats a plant, contact poison control or a vet. Check your local invasive species list before planting anything with a spread warning.