by Leslie Cox; Wednesday; January 18, 2017

What better way to celebrate the role bees and butterflies play in our gardens than to select a native perennial plant which nurtures them and name it Plant of the Year for 2017?

Introducing Aslepias tuberosa…better known as butterfly weed. Or you may be more familiar with one of its other common names: butterfly flower, chigger flower, Indian potato, pleurisy root, swallow root…and a few more.

This North American native wildflower is a main food plant for Monarch butterflies. Queen butterflies, hummingbirds, bees and other insects are also attracted. Small wonder, as the flowers produce copious amounts of nectar. (The indigenous people and first settlers to North America collected the nectar to use as a sweetener.)

The whole plant is quite striking with its upright stature and light green leaves showing off the bright orange blossoms to advantage…although there are colour variations within this species, ranging from deep red-orange to yellow.

The milky sap found in the Aslepias genus, as well as in several other plant families such as Euphorbia, is toxic to varying extents…depending on the species. It is one of the three forms of defense this family of plants has against predators. However, the difference in sap composition contained in Asclepias tuberosa lowers this particular plant’s toxicity level enough for Monarch butterfly larvae to feast on the leaves safely. Although…they too, have built up a tolerance to the toxicity levels of other plant species in this plant family.

One other notable feature of these milkweed plants worth mentioning is the floss- or silk-like fibres found attached to each seed. These fibres, or filaments, form in clusters, called coma, for each individual seed and are designed to catch the wind for seed dispersal.

These filaments are hollow…making them a good source for insulation purposes in some products. They are also coated with a wax-like substance. These qualities made milkweed silk an ideal substitute for kapok in making masses of lifejackets and other personal flotation equipment for the soldiers fighting in World War II.

Back to the botany stats on this plant…

Asclepias tuberosa is an herbaceous perennial. It is slow growing to about three feet (90 cm) tall and roughly two feet (60 cm) wide. Patience is needed if starting from seed as it can take up to three years for flowers to appear.

Do be careful where you place it in the garden as it is not partial to transplanting. But if you are careful, and dig down far enough, you can transplant your specimen successfully. Be forewarned! Leave a piece of root behind in the old spot and another plant will sprout up…just like any of the hardy mints: peppermint, spearmint, ginger mint.

It is also a good idea to deadhead the spent flowers throughout the growing season to prevent masses of young plants from developing.

Sounds like a lot of work. But for the benefit of our pollinating insects, it is a worthy addition to the garden inventory. I plan to add at least one butterfly weed plant to my landscape this year in the hopes of enticing another Monarch butterfly into our garden. It was so thrilling to see our very first one last year. I suspect it could possibly have come from a batch of butterfly cocoons raised by the students at Miracle Beach Elementary school…although the school is about six km away.

Here’s hoping the students will raise another brood again this year!

But wait! There is more good news about Asclepias tuberosa!

If feeding the butterflies has not enticed you to add this plant species to your garden…perhaps you would be interested to know this very plant is reportedly good at repelling wireworms away from your prize plants, susceptible vegetables, and fruits such as strawberries. Or, rather a crude extract from this plant, as studied by Villani and Gould (1985) with decent results. This particular part of their overall research revealed significant success at thwarting wireworms feeding on seeds which had been soaked in a crude extract of Asclepias tuberosa before sowing.

There is one caveat. I have been unable to verify whether the plant extract they used has ever been approved for use by either the EPA or CFIA.