The Asclepias Genus (Milkweed)

Part of the dogbane plant family, Apocynaceae, the Asclepias genus comes from the Americas.

There are roughly 200 different species of herbaceous perennials which come under the milkweed genus, notable for their globular clusters of tiny, starry flowers.

Milkweed At A Glance

Asclepias plants attract a multitude of pollinators, and feature unusual flowers. 

These flowers are specifically designed to make pollinators’ legs get stuck in a well of pollen, meaning that once they pull their feet out and go to land on the next flower, the pollen transfers on contact, which is a clever way of ensuring the plant’s survival.

As these form part of the dogbane family, it’s important to note that milkweeds contain a dangerous, white sap which is poisonous to many animals, and therefore these plants aren’t suitable for gardens which have pets or children.

Asclepias Name Origin

The genus name stems from the Greek deity of medicine, Asclepius, as these plants have many historical medicine applications.

The common name for most of these plants, milkweed, comes from the sap within the plant, and this oozes out when the plant gets injured.

This is one of the plant’s natural defenses, and more than a few insects and animals have become immune to its defenses, and these chemicals don’t seem to affect the pollinators who extract the nectar, either. 

Milkweed Flower Symbolism

Asclepias flowers represent grace, remembrance, freedom, and dignity.

Clever Pollination Tactics

The closer you look at nature and its quirks, the more fascinating it becomes.

With the plants belonging to the milkweed genus, this is especially true in the way the plants are pollinated.

To look at how the flowers are pollinated, it’s worth looking at the structure of the flower, as the design is quite sophisticated.

Each tiny flower has five sepals and five petals. In some species, the flowers feature a corona, which has five boat-shaped hoods.

These hoods feature pointed horns, which are filaments and in some cultivars, they are clearly visible, adding to the flower’s beauty. 

The anthers divide into two, and they rejoin at the top of the stigma, which itself is a little unstable.

The pollen forms in sacs just underneath the stigma.

When a pollinator lands on the bloom, at least one foot slips into the pollen sacs through the stigma slit.

When the insect wrenches it out again, a load of pollen comes with it. 

The pollen is sticky enough that it is carried to the next flower, (hopefully another milkweed) and when the insect lands on the new bloom, the flower is pollinated.

It’s interesting to note that not all insects have the brute force to pull their own legs from the pollen sacs.

Sadly, some will stay trapped on top of the flower, or they have to remove their own legs to escape.

In a more grim tone, this is probably a way that the flowers ensure the pollen stays reserved for the intended pollinators, helping to ensure that the plants carry on their genetic line.

Monarch Butterflies And Milkweed

It’s worth knowing that milkweed plants are the only host plants for Monarch butterflies, or Danaus plexippus

Regardless of whether you have a dedicated butterfly garden or not, these plants are vital for monarch butterflies, and planting them in your garden, or preserving them, helps to sustain them.

Monarch butterflies use milkweed plants as a source of food and shelter, but they also lay their eggs on it, giving the larvae a much-needed source of food while they are too young to find it themselves.

The toxic chemicals within the sap also help the butterflies. Sounds strange, doesn’t it?

The butterflies absorb the chemicals, which in turn, makes the caterpillars and the butterflies poisonous to predators, and gives them a bitter taste, making the predators avoid them.

Queen butterflies also use the milkweed plant as a host for their larvae, as well as a source of food.

It’s worth noting that only certain species of milkweed are popular with monarch butterflies, and you do have to be careful where you grow them.

This is because if you grow them at the wrong time, or the wrong place, you can actually cause damage to monarch butterfly populations.

It disrupts the migration patterns of these insects, and there is some evidence to suggest that improper planting can cause the numbers of the butterfly parasite Ophryocystis elektroscirrha to soar.

Milkweed As An Invasive Species

It’s worth noting that milkweed has the potential to become very invasive, and if you aren’t careful in picking the right variety, it can take over your garden.

One of the least invasive types – in fact, it isn’t classed as invasive at all – is the swamp milkweed, which will help attract butterflies and other pollinators, but it won’t cover your garden.

Milkweed Uses 

Asclepias plants have been used throughout history for a variety of medical applications.

Common Milkweed plants have been used to treat lung problems such as bronchitis, asthma, and other complaints like wounds, scrapes, sore throats, fevers, and rheumatism.

Milkweed floss, which is the seed fibers of the common milkweed, can be gathered as a hypoallergenic filling or insulation, and does particularly well when it’s combined with down.

It’s also used in thermal insulation, oil absorbents, and acoustic insulation, and can be used for tinder, too.

The stems produce fibers, which are useful too. In the past, they’ve been used to produce fabric, netting, bow strings, ropes, fishing lines, and baskets.

Some milkweed species were used by Native Americans for food, by boiling the leaves, buds, shoots, and flowers.

They had to be prepared very carefully, and only taken from certain species, and don’t really have many medical or culinary uses today.

Asclepias Growing Requirements

Asclepias perennials are hardy in USDA zones 3 through to 9, and bloom in summer until fall, making them a great option for introducing color into any garden.

The flowers are available in hues of yellow, white, orange, purple, pink, and red, depending on the species you choose.

The height of these plants is ultimately determined by the species and the growing conditions, and can vary between one and 6 feet high.

These plants need soil with plenty of drainage above all else, preferably with a pH between 5.0 and 7.0.

Asclepias are sun-loving plants, so make sure you pick a sunny site for them, where they can produce plenty of flowers for pollinators to visit.

Provided that your area gets an average amount of rainfall, these plants will largely take care of themselves, and you won’t need to dedicate much time to maintaining them either.

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