Milkweeds

One of my early memories as a child is setting in the hayfield with grandpa as he showed me different plants.  I have a clear memory of him cutting off a plant with his pocket knife and it oozing out a thick white sap.  "It looks like milk, doesn't it?  We call it milkweed.  If a cow eats too much of it, it can make them sick."  I don't know what 3 or 4 year old me was supposed to do with that information, but it became one of those core memories that helped spark my interest in plants and biology.

Their milky sap aside, milkweeds are important plants for pollinators.  Their long-lived summer blooms provide copious amounts of nectar that attract butterflies in particular.  One species, asclepias tuberosa, is known as butterfly weed.  Here at Bob's, we just got in a shipment of butterfly weed for our retail locations.  These perennials make a great addition to your landscape.

There are two ways to grow butterfly weed - from a potted nursery-grown plant or directly from seed.  However, when growing them from seed, some care needs to be taken.  The seeds need to be pre-chilled for at least 7 to 10 days by keeping them in the fridge until time to plant.  This mimics them enduring the cold winter outside and is a biological cue for them to start growing.  Once sprouted, butterfly weed grown from seed will usually not bloom in its first year.

Butterfly weed along with all milkweeds are part of the genus asclepias.  They are herbaceous perennials that produce a white, latex containing sap from which they get their name.  This is where the sick cows come in.  All parts of the plant contain toxic cardiac glycosides, which can cause nausea, diarrhea, weakness, and confusion in small amounts, and seizures, heart rhythm changes, respiratory paralysis, and even death in large amounts.  However, have no fear when it comes to children or pets eating your milkweed.  The sap is extremely bitter and the leaves are quite prickly.  This also makes them deer resistant!

The only thing that might eat your milkweeds are monarch butterfly caterpillars, but that's a good thing!  The whole point of growing these plants is to support butterfly populations.  Pretty blooms are just a bonus.  Even if the caterpillars have eaten all the leaves and the plant is just stems, after a while, new leaves will sprout and grow.

The asclepias family of plants is named after the Greek God of Medicine. Asclepius was a son of Apollo and he wielded a unique staff that we are all familiar with today. The Rod of Asclepius was a wooden staff with a snake wrapped around it. Over the centuries it has become the symbol for medical professionals everywhere.

The plants have long been used in herbal medicine, where they're also known as Pleurisy Root.  Native Americans and pioneers would use extracts from the roots of some milkweed species to treat lung inflammations, or pleurisy.  The active toxin in the sap are cardiac glycosides.  Cardiac glycosides are a class of organic compounds that increase the output force of the heart and increase its rate of contractions by acting on the cellular sodium-potassium ATPase pump. As medicines they are used for treating heart failure and certain irregular heartbeats.  Digoxin is another cardiac glycoside that is derived from digitalis, foxglove.

From pollinators, to pioneers, to a paean god, milkweeds are plants that have a unique story behind them.  If you're looking for a perennial that will offer beautiful color while attracting beautiful wildlife all summer long, this is a plant to consider.  It will definitely make a welcome addition to my own landscape.