Asclepias, also known as Milkweed, is a genus of about200 species of herbaceous perennials in the family Apocynaceae, native to Americas.
Milkweeds produce star-shaped flowers that appear in clusters on tall woody stems. These perennials are known for their sweet-smelling flowers and milky white liquid within its foliage. They are attractive to butterflies, bees and other insects.
The genus name comes from the Greek god of medicine, Asclepius, because of the plants’ medicinal properties.
The common name “Milkweed” is a reference to the milky sap which can be seen if the stem or leaf is broken.
Despite of their name, they are actually beneficial wildflowers, and at least five species are listed as endangered species in the U.S.
Milkweeds symbolize remembrance, dignity and freedom.
Interesting facts about Asclepias:
The flowers of Milkweed species are beautiful and structurally complex.
Each individual flower has a five-parted calyx (sepals) and a five-parted corolla (petals), plus in some species a corona that looks like an extra set of petals. The corona often has five upright hoods, which are usually rigid, boat-shaped and brightly colored. Each hood often contains a pointed, incurved horn, which is the modified filaments of a flower’s anthers. Some of the horns are visible on some species and nearly invisible on others. The anthers (pollen-bearing portion of the stamens) are split into two halves, and each two adjacent half-anthers are connected at the corpusculum (a gland that assists in transporting pollen), which sits atop the stigma slit. The plant produces its pollen in little packets called pollinia (pollen sacs), which are designed to stick to an insect’s leg, waiting to be accidentally snagged and carried off.
Unusual Pollination Strategy
Milkweeds are pollinated in a more specific way than most other insect-visited flowers.
When insects land on their flowers, clinging to the petals as they feed on nectar, a foot slips into the stigmatic slit and comes in contact with a sticky ball of pollen, called a pollinium. When the insects is ready to move on, it must extract its leg, taking the pollinarium (two pollinia joined via translator arms to a corpusculum) with it to the next flower. If the flower is lucky, the insect will travel to another Milkweed flower and deliver the pollinia. Any insect strong enough to remove the sac can fertilize another plant. However, some insects are not strong enough to remove their legs from the anther slits with the attached pollinia and are trapped to die there, or they must tear off their own limbs to escape.
Milkweed as a Host Plant
Milkweeds are the sole host plants for Monarch butterflies (Danaus plexippus).
Monarch butterflies, also known as the milkweed butterflies, can’t live without Milkweed. They rely on it for food, shelter and a place to lay their eggs. Milkweeds provide all sorts of nutrients that help the Monarch caterpillars to transform into beautiful butterflies. But they are much more than just food for these caterpillars. Monarch butterflies store the plants’ chemicals in their bodies, which give them protection from predators, because the sap found in the plants makes the caterpillars and later, the butterflies, toxic and bitter-tasting to many predators.
As a host plant, Milkweeds are only used by Monarch and Queen butterflies, but as a nectar plant they are attractive to many butterflies and other insects.
Offering a wide array of native nectar plants will attract Monarch butterflies and many other pollinators to your garden. However, the name “Milkweed” can discourage landowners to keep them as the term may suggest that the plant is invasive.
Is Milkweed Poisonous?
It’s worth to mention that Milkweed contains toxins that can be harmful to pets, livestock and even people. Not all species are poisonous, but it’s important to know what you’re doing. Species with whorled, narrow leaves are typically more toxic than species with broad leaves. Although edible, this plant can be confused with other poisonous species, so be careful!
Benefits and Uses
Asclepias have a long history of being used formedicinal purposes.
They have been used to treat various ailments such as sore throats, fever, skin ulcers, eczema, tumors, sores, wounds, rheumatism, diarrhoea, colic, bronchitis, asthma and other respiratory problems. The plant was also used to expel tapeworms, to cure snake bites. and as a contraceptive. The common milkweed (Asclepias syriaca) is an excellent herb for the treatment of lung conditions.
Milkweeds have been used as a foodsource by Native Americans and early settlers. They boiled and ate leaves, buds, flowers and young shoots. Due to all its natural benefits, Milkweed is regarded as a nutritious and wild vegetable high in vitamin C and Beta Carotene. Nearly every part is edible, but each must be harvested and prepared properly.
Today, the plant has limited medicinal and culinary uses.
However, this plant has been used not only as a food and medicine, but also for many various things.
The fibers from Milkweed stems have been used for thousands of years to produce textiles, cordage, netting, bow strings and fishing lines. Native Americans used fiber in the stems for baskets, ropes and nets.
The floss, attached to brown seeds, can be used as stuffing for pillows, mattresses, and quilts or carried for tinder.
During World War II, the US Army paid kids to collect Milkweed’s fluffy white floss, which was then used for filling in flotation vests for the military personnel. Each life vest required two bags of pods, inspiring the slogan “Two Bags Save One Life”. During this time, the navy made 1.2 million life jackets from Milkweed seed floss. Milkweed was often the only thing that kept a sailor or downed aviator from slipping beneath the waves.
These flowers come in shades of red, purple, pink, orange, yellow and white.
The plant reaches heights of 30 cm (1 ft) to 180 cm (6 ft).
Asclepias thrive best in well-drained soil, with a pH range of 5.0 to 7.0.