The Asclepias tuberosa is native to North America and belongs to the dogbane family (Apocynaceae). The Aclepiadaceae is considered a subfamily of Apocynaceae. Asclepias tuberosa is a species of milkweed. It is called butterfly weed because it attracts a lot of butterflies with its colour and copious production of nectar. Not only butterflies but also bumblebees, bees and other insects are attracted by this wonderful perennial.
Unlike many other milkweeds the Asclepias tuberosa has no milky sapped stems. That it is why it is more often called butterfly weed instead of butterfly milkweed.
Every winter the stems and leaves die back to the ground. Because the new growth emerges at the end of April you can combine it well with early flowering bulbs like crocuses or daffodils. By the time the bulbs have withered the Asclepias tuberosa arises. That way there will not be an empty spot after the leaves of the bulbs have died off. Slugs and snails enjoy the newly growing stems, so be cautious during that time. After the stems have reached a height of about 20 centimetres (8 inches) they leave the plant alone in my garden.
The butterfly weed has hairy stems that usually stay upright without support. This perennial blooms for a long time and produces clusters of long lasting bright orange flowers. You can use them as cut flowers or in dried floral arrangements.
The flowers give way to spindle shaped seed pods. One year more seed pods are formed than the other year even though the flowers were visited by many insects. The seed pods split open when they are ripe releasing numerous silky-tailed seeds for dispersal by the wind. Most of the seeds drop to the ground near the original plants in my garden.
The Asclepias tuberosa is easily propagated by seed. Most of the seeds that have dropped on the ground will start to grow. You do not have to do anything special for this. You can also plant the seeds in a new spot where you want to grow a new butterfly weed.
The average height of the butterfly weed is about 70 centimetres (28 inches). I have placed it in a warm dry and sheltered spot and it grows up to about 90 centimetres (35 inches) there.
The Asclepias tuberosa has a tuberous rootstock and grows in a clump that slowly spreads. Due to its deep taproot the plant is not easily transplanted. Because of the deep taproot the butterfly weed is very drought tolerant. The butterfly weed prefers dry, well-drained, sandy soil and a sunny spot, but it grows in any type of soil as long as it is well-drained. You should not pamper this plant.
Attracts bees: yes
Characteristic: newly emerging every year
Exposure: sun/part shade
Flower colour: orange
Flowering time: May – July
Foliage colour: green
Fragrant flower: no
Hardiness: -20 ºC/-4 ºF
Height: 70 cm/28 inches
Soil: normal/dry