Bluestar 'Storm Cloud'
Amsonia tabernaemontana 'Storm Cloud' · Apocynaceae
New shoots emerge near-black in spring, opening to dark olive leaves with silver veins under clouds of starry, periwinkle-blue flowers.
- Size
- 2½ ft tall, 3½ ft wide
- Zones
- 4 to 9
- Light
- Full sun to part sun
- Flowers
- Mid May to mid June
- Pets
- No toxicity recorded
- Job in a bed
- Drift
A bed built around bluestar 'Storm Cloud'
The planner designed this bed around bluestar 'Storm Cloud' when this page was made: a 12 × 6 ft (3.7 × 1.8 m) English border in zone 6, full sun. It chose the other plants from the 966 that suit those conditions, and says below why bluestar 'Storm Cloud' stands where it does.
The plants
- 1 Bluestar 'Storm Cloud' × 1, blue
- 2 Moor grass 'Greenlee' × 5, tan
- 3 October daphne × 8, pink
- 4 Wild quinine × 3, white
- 5 Brown-eyed Susan × 5, yellow
- 6 Spurge 'Blackbird' × 3, purple leaves
- 7 Star of Persia × 3, purple
- 8 Spring starflower × 12, blue
Why this plant
- The only airy sprays. The others are spires, dense clusters, flat plates and others. Shape reads at a distance, where colours blur.
Why here
- In the middle. At 2½ ft it is seen over October daphne (8 in) in front of it.
- One plant, alone. A feature plant is seen as an object, and needs clear ground around it.
Why now
- In flower for five weeks. From mid May to mid June.
- Part of the bed's peak. With moor grass 'Greenlee' and star of Persia in late May: 3 kinds at once. No week has more.
Planned as an English border: 6 of the 6 groups (100%) are drifts, longer along the bed than they are deep. The flowering is at its height from late May, with 3 kinds out together. The bed is balanced: the left half carries 51% of the visual weight and the right half 49%.
The planner's own design check: 13 Excellent, 4 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 bluestar 'Storm Cloud' goes in a border
At 2½ ft it belongs in the middle of a bed. In the planner's ten height classes it is medium (24 in to 2½ ft).
Its job: drift. Planted in a small group of three or five, and repeated further along in the other number.
A bluestar with three seasons of interest: black stems in spring, blue flowers in May, and a clean, shrub-like mound afterwards. It takes years to bulk up and then lives for decades untouched.
- A long-lived mound for the middle of a border
- Dark spring stems with bulbs
- Low-care planting
What to plant with bluestar 'Storm Cloud'
Plants recorded as good partners for it, and what each pairing does:
- Peony: in flower together for three weeks, from late May.
- Siberian iris: in flower together for three weeks, from late May.
- Prairie dropseed: carries the spot on into mid September.
Questions about bluestar 'Storm Cloud'
Does bluestar 'Storm Cloud' need sun or shade?
Bluestar 'Storm Cloud' 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. Once settled in, it stands drought.
What zones does bluestar 'Storm Cloud' grow in?
USDA zones 4 to 9. It is hardy to zone 4, which means it survives winter nights down to about −20 °F (−29 °C).
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does bluestar 'Storm Cloud' flower in my zone?
In zone 5 it flowers mid May to mid June. As a spring flower it moves about a week for every zone: earlier where it is warmer, later where it is colder.
| Zone 4 | Late May to late June |
|---|---|
| Zone 5 | Mid May to mid June |
| Zone 6 | Early May to mid June |
| Zone 7 | Early May to early June |
| Zone 8 | Late April to early June |
| Zone 9 | Mid 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 bluestar 'Storm Cloud' be planted?
2½ ft (80 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 3½ ft (100 cm), so a group knits into one patch.
It grows 2½ ft (70 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many bluestar 'Storm Cloud' plants do I need?
At 2½ ft apart, set out in staggered rows:
- 2 to fill 10 square feet (about 1 m²)
- 4 for a single row 10 ft (3 m) long
- 5 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as a group of three or five, with a second group further along in the other number.
In the bed above, the planner used one in one group.
Is bluestar 'Storm Cloud' poisonous to dogs and cats?
No toxicity is recorded for dogs, cats, horses or people, according to NC State Extension.
"Not toxic" is not "edible": a pet that eats a lot of any plant can be sick.
Do deer eat bluestar 'Storm Cloud'?
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 bluestar 'Storm Cloud'?
Bluestar 'Storm Cloud' is over by mid June. These start as it finishes and carry the same spot on, so it never goes flat:
- Black-eyed Susan: from mid July to mid September, 24 in tall.
- Butterfly weed: from late June to early August, 24 in tall.
- Yarrow: from mid June to late August, 24 in tall.
What does bluestar 'Storm Cloud' look like in winter?
Bluestar 'Storm Cloud' 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 bluestar 'Storm Cloud' good for bees and butterflies?
Bluestar 'Storm Cloud' is visited by pollinators and butterflies.
It is native to the United States (this is a named variety of the native plant).
More Amsonia
- Arkansas bluestar Amsonia hubrichtii
- Bluestar Amsonia tabernaemontana
- Bluestar 'Blue Ice' Amsonia 'Blue Ice'
In these guides
- Deer-resistant perennials for full sun
- Drought-tolerant perennials for full sun
- Pet-safe plants for a sunny border
- Native perennials for pollinators
- Plants for butterflies
- Plants with blue flowers
Zone guides: Zone 4 · Zone 5 · Zone 6 · Zone 7 · Zone 8 · Zone 9
Every fact on record
- Type
- Perennial
- Size
- 2½ ft (70 cm) tall, 3½ ft (100 cm) wide
- Plant
- 2½ ft (80 cm) apart
- Height class
- Medium (24 in to 2½ ft)
- Place in the bed
- Middle
- Flowers
- Mid May to mid June; airy sprays; blue
- Leaves
- Medium texture, herbaceous; dark green
- Shape
- Mounding, clumping
- Hardy in
- USDA zones 4 to 9
- Light
- Full sun, part sun
- Soil
- Average, well-drained
- Water
- Moderate
- Feeding
- None needed
- Family
- Apocynaceae
- Comes from
- Central & Eastern U.S.A
- Attracts
- Pollinators, butterflies
- Stands up to
- Deer, drought
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.