How to Grow Asclepias Plants in your Garden

Gardener's HQ Guide to Growing Milkweed, Pleurisy Root, and Butterfly weed

Plants from the Asclepias plant genus tend to be either half hardy or hardy perennials.

Some of the common names for members of Asclepias include Butterfly weed, Milkweed, Orange Milkweed, and Pleurisy root.

Milkweed plants normally flower in the summer.

Description of Milkweed and other Asclepias

Asclepias are often subshrub like in nature, and the they range in size from 30 cm to 2 metres (1 to 7 feet).


They are often grown in wildlife gardens as they are plants that are very attractive to butterflies (especially the monarch).

Asclepias tuberosa
Asclepias tuberosa (Butterfly Milkweed).

Milkweed family members have clusters of blooms in red, orange, or other hot colour's.

Asclepias incarnata
Asclepias incarnata (Swamp Milkweed). Both photographs by Gmayfield10.

They make an ideal plant to grow when trying to plant a natural looking or butterfly garden.

Commonly Grown Asclepias Species Photographs and Plant Identification

Asclepias tuberosa

Asclepias tuberosa
Asclepias tuberosa (Butterfly Weed), photograph by Frank Mayfield; CC.

Also see my How to grow Asclepias tuberosa guide.

Asclepias curassavica

Asclepias curassavica
Asclepias curassavica (Tropical Milkweed / Bloodflower / Cotton Bush), photograph by jimduggan24; CC.

Also see my Asclepias curassavica plant growing guide guide.

Asclepias syriaca

Asclepias syriaca
Asclepias syriaca (Common Milkweed / Butterfly Flower / Silkweed), picture by Peganum; CC.

Also see Asclepias syriaca growing guide.

Asclepias Growing and Care Guide

Common Names: Milkweed, Butterfly Weed, Pleurisy Root, Swan Plant Balloon Plant. Milkweed: Common; White; Whitestem; California; Tropical; Scarlet; Purple; Desert; Poke; Blunt-leaved;Narrow leaf; Heart-leaf.
Family: Apocynaceae
Life Cycle: Hardy Perennial, Half Hardy Perennial
Height: 12 to 72 inches (30 to 180 cm)
Native: Americas, Africa, Europe, Asia

Growing Region: Zones 3 to 10
Flowers: Summer
Flower Details: Many colour's, especially: Yellow, Orange, Red, White, Cream. Clustered flowers
Foliage: Dark green, lance shaped

Sow Outdoors: Cover seeds. Start of spring or autumn. Spacing 12 to 24 inches (30 to 60cm)
Sow Indoors: Chill seeds in the fridge for three weeks in peat pots (within plastic bags). Germination time: one to three months in the light. Temperature 55 to 75°F (13 to 24°C). Transplant outdoors before the last frost of spring or in the autumn.

Requirements: Full Sunlight or light shade. Sandy soils. Many species are drought resistant. Pinch back when 5 or 6 inches (12 to 15cm) tall to encourage bushy growth. Divide tubers in Spring; this is a risky process as roots are delicate.

How to Grow Asclepias

When planting Asclepias plants outdoors, it is best to sow out the seeds in either early spring or autumn. Once sown, lightly cover the seeds with soil.

If you plan to start the growing of milkweed and other Asclepias genus plants indoors, then you first should imbibe the seeds in the fridge for three weeks in soil, then sow them into peat pots.

Ideally you should do this 10 weeks before you plan to transplant them outdoors, normally in the late spring (or at the beginning of Autumn).

Germination of milkweed seeds normally takes about one to three months. Germination should be performed at a temperature between ten and twenty degrees Celsius (50 and 68°F).

Outdoors, the seedlings should be planted with a spacing of about 40 to 50 cm (16 to 20 inches). Locate in partly shaded to fully sunny parts of your garden. Asclepias plants prefer to grow in a sandy soil, but will grow in most non-heavy soils.

Caring for Milkweed and other Asclepias

Milkweed is very easy to look after, pinch back the heads when about 12 cm (5 inches) high. This will enable auxin hormones to make more heads (instead of having a single flower).

If you require more Asclepias plants, then you should (very) carefully take root cuttings in the spring.

I hope that you enjoyed this guide on Asclepias. You may also enjoy the following Gardener's HQ growing guides: How to grow Oxypetalum, Delphinium

, Cyclamen plant, and Vinca minor plants.