Asclepias syriaca
Silkweed, Common milkweed
- Height × spread
- 1.2m × 0.5m
- Position
- Full sun
- Hardiness
- Heated greenhouse 5C & above (RHS H1c)
- Flowers
- Summer
Availability
Please ask in store about availability
Many plants are seasonal. Call 01234 567890 to check current stock.
About this plant
A sturdy plant with quite large, smooth-looking leaves. They are coloured dull green, are oblong in shape and are held in pairs, standing out on the upright stems. They have noticeable pink tinted midribs. The leaves have fine hairs on their undersides. There are small clusters of flowers from June to August which are coloured purple-green and are delightfully scented. The flowers are followed by pear-shaped pods that release seeds that dangle from silken threads. The plant grows wild in scrubby and waste places and is common in America, New England, and the southern part of Canada where it is found in association with golden rod and Michaelmas daisies. The young shoots are edible, although some species have a milky latex in the stems which can be poisonous. The dead winter stems are loved by flower arrangers.
- Flower colour
- Purple
- Foliage colour
- Green
- Variegated
- No
- Scent
- Yes, honey-almond
- Shape
- Column
- Height
- 1.2m
- Spread
- 0.5m
- Season of interest
- Summer
- Flowers in
- Summer
- Evergreen
- Deciduous
- Garden style
- Wild flower meadow, Prairie garden
- Sun or shade
- Likes full sun, tolerates part shade
- Soil type
- Chalk, Loam (normal)
- Soil pH
- All types
- Drainage
- Moisture retentive soil, Well drained soil
- Hardiness
- Heated greenhouse 5C & above (RHS H1c)
- Borders & containers
- Borders
- Use for
- Ground cover, Bee attraction, Butterfly attraction
- Hazards
- Yes, potentially harmful; Humans: Harmful if eaten
Spring
Spring - late · Outdoors
Feed with slow release fertiliser
Apply a general purpose slow release fertiliser, spreading it around the root area of the plant as it is coming into growth. (Or apply a liquid feed at regular intervals throughout the growing season.)
This is a simple way to provide a nutrient boost as a single annual procedure.
Spring-Autumn · Outdoors
Water frequently to keep the soil moist
The plant thrives in moist or boggy soil, doesn't tolerate dryness and should be watered frequently, not only after a period of drought, but if the soil begins to dry out spring to autumn. Check plants in pots more frequently, especially in hot weather.
Spring - early-mid · Planting
Divide when too large
The plant can be divided if it becomes too large or another plant is required. This may involve physically dividing the clump in two, removing offsets or small bulbs or dividing rhizomes. The new plants can be grown in pots or planted in the ground.
Found in
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