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.
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 (Butterfly Milkweed).
Milkweed family members have clusters of blooms in red, orange, or other hot colour's.
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.
Asclepias tuberosa (Butterfly Weed), photograph by Frank Mayfield; CC.
Also see my How to grow Asclepias tuberosa guide.
Asclepias curassavica (Tropical Milkweed / Bloodflower / Cotton Bush), photograph by jimduggan24; CC.
Also see my Asclepias curassavica plant growing guide guide.
Asclepias syriaca (Common Milkweed / Butterfly Flower / Silkweed), picture by Peganum; CC.
Also see Asclepias syriaca growing guide.
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.
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.Cyclamen plant, and Vinca minor plants.