Showy milkweed
Asclepias speciosa · Apocynaceae
The gardener's calendar
Ideal time to plant showy milkweed: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Foliage
- Deciduous
- Flowering
- June to August
- Adult size
- 0.9 to 1.5 m in height
- Growth
- Moderate to fast
- Hardiness
- Hardy to -15 °C
- Origin
- North America (west)
- Soil type
- Well-draining, tolerates dry soils
Care
Sunlight
Install your milkweed in full sun for generous flowering (minimum 6 hours of direct light). It tolerates partial shade but will flower less abundantly. Avoid areas too exposed to strong winds that can damage the stems.
Watering
Water regularly during the first year of establishment. Once well-rooted, this plant becomes very tolerant of drought and only needs watering during prolonged periods without rain. In winter, stop all watering.
Soil and drainage
Prefer well-draining, light, and even poor soil. Milkweed adapts to various soil types but dreads waterlogged conditions that can cause root rot. Adding sand or gravel improves drainage if your soil is clayey.
Fertilizer
Undemanding, this plant generally doesn't need fertilizer in average soil. If you wish to stimulate flowering, a light application of balanced fertilizer in spring is enough. Avoid excess nitrogen which promotes foliage at the expense of flowers.
Pruning and maintenance
Prune lightly in spring to maintain a compact shape and remove damaged stems. In late autumn, cut the plant back to ground level to prepare for winter. Leave the seed pods in place at the end of the season: they dry naturally and disperse seeds.
Diseases and pests
Milkweed is generally robust. Be careful however of excessive moisture which can promote rot or fungi. Good air circulation and well-draining soil prevent most problems. Check regularly that no pests settle on the leaves.
Did you know?
The beautiful milkweed is one of the main host plants of the monarch butterfly, an emblematic North American butterfly: the caterpillars feed exclusively on its leaves and accumulate its natural toxins to protect themselves from predators. This fascinating relationship makes it an essential plant for creating wildlife-friendly gardens.
Where to buy it
Plant in spring or early autumn, avoiding spells of intense heat. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, April, May, September.
Add this plant to my garden →Plants from the same family
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Tips generated and checked by Viridia — adapt them to your local climate.