Overview
Asclepias speciosa is a bushy bulbs in the genus Asclepias, part of the Apocynaceae family, with deciduous foliage. It typically grows around 0.8 m tall. Asclepias speciosa grows best in full sun, and tolerates most soils and any pH. Its UK hardiness is rated H4. Suggested uses include city and courtyard gardens, cottage and informal garden and prairie planting. It is native to Alberta, Arizona, British Columbia, California, Colorado, Idaho, Iowa, Kansas, Manitoba, Minnesota, Montana and Nebraska.
About
Asclepias speciosa is a milky-sapped perennial plant in the dogbane family (Apocynaceae), known commonly as the showy milkweed and is found in the western half of North America. It is native to North America, Alberta, Arizona, British Columbia, California and other regions. In the garden it prefers full sun and most soil types. In UK gardens it is hardy through an average UK winter (RHS H4). Suggested uses include city and courtyard gardens, cottage and informal garden and prairie planting. It tolerates soil of any pH, moist but well-drained, poorly-drained conditions and south-facing and west-facing aspects. Plant in well-drained soil in sun or partial shade.
Wikipedia contributors, CC BY-SA 4.0 — Asclepias speciosa
About the genus
Asclepias is a genus of herbaceous, perennial, flowering plants known as milkweeds, named for their latex, a milky substance containing cardiac glycosides termed cardenolides, exuded where cells are damaged. Most species are toxic to humans and many other species, primarily due to the presence of cardenolides. However, as with many such plants, some species feed upon milkweed leaves or the nectar from their flowers.
Wikipedia contributors, "Asclepias", CC BY-SA 4.0 — Asclepias
Growing conditions
Best soil and position for Asclepias
- Sunlight
- Full sun
- Soil type
- Clay, Loam, Sand
- Soil pH
- Acid, Alkaline, Neutral
- Soil moisture
- Moist but well-drained, Poorly-drained
- Aspect
- South-facing, West-facing
- Exposure
- Sheltered
- UK hardiness
- H4
Plant details
Asclepias speciosa size, habit and characteristics
- Plant type
- Bulbs, Herbaceous Perennial
- Habit
- Bushy
- Foliage
- Deciduous
- Height
- 0.8 m
- Suggested uses
- City and courtyard gardens, Cottage and informal garden, Prairie planting
- Native to
- Alberta, Arizona, British Columbia, California, Colorado, Idaho, Iowa, Kansas, Manitoba, Minnesota, Montana, Nebraska
- Toxicity
- Toxic if ingested
Care notes
Pruning and caring for Asclepias speciosa
- Cultivation
- Plant in well-drained soil in sun or partial shade. Tolerates soil of any pH and moist but well-drained or poorly-drained conditions. Suitable for city and courtyard gardens, cottage and informal gardens, and prairie planting.
- Propagation
- Propagate by seed or by division, or root basal cuttings in spring
- Pest resistance
- Generally pest-free
- Disease resistance
- Generally disease-free
Frequently asked questions
How do I grow Asclepias speciosa?
Plant in well-drained soil in sun or partial shade. Tolerates soil of any pH and moist but well-drained or poorly-drained conditions. Suitable for city and courtyard gardens, cottage and informal gardens, and prairie planting.
Where is the best place to plant Asclepias speciosa?
Asclepias speciosa prefers full sun. It suits sheltered positions.
What soil does Asclepias speciosa need?
Asclepias speciosa is adaptable and grows happily in most soil types, including clay, loam and sand. It is happy in soil of any pH. Aim for soil that stays moist but well-drained to poorly-drained.
How big does Asclepias speciosa grow?
Asclepias speciosa reaches a height of 0.8 m.
Is Asclepias speciosa hardy in the UK?
Asclepias speciosa has an RHS hardiness rating of H4, meaning it is hardy through an average UK winter, tolerating -10 to -5°C.
How do I propagate Asclepias speciosa?
Propagate by seed or by division, or root basal cuttings in spring.
Is Asclepias speciosa toxic?
Toxic if ingested.
