Tropical Milkweed

Asked February 24, 2019, 10:35 AM EST

Good morning, I would love to plant some milkweed to attract and help the Monarchs, but I’ve Read about the Asclepias as being dangerous. What is your opinion or what can you recommend? Thank you Sue Essen Hopkins

Hennepin County Minnesota milkweed

3 Responses

Thanks for the question. Milkweed (Asclepias) receives much attention from gardeners as it provides an excellent nesting plant for monarch butterflies as well as various other pollinators. Like many plants that are found in our gardens (rhubarb, rhododendron, hydrangea, foxglove, morning glory, lily-in-the-valley, etc.), milkweed can be discomforting to humans if it is eaten and CONSUMED IN LARGE QUANTITIES.

Most common species of Asclepias contain cardiac glycosides. These compounds increase the force of heart muscle contraction while reducing heart rate. This is why cardiac glycosides are a type of heart stimulant. If unchecked and in rare instances, the results can be fatal. However, and this is important to stress, this danger can only arise if the plant is eaten in huge amounts. Its mere presence in a garden does not pose any danger. One precaution that should be taken is to wash off any of the milkweed's white liquid that might be on one’s skin and/or clothing after handing the plant.

Here is an article that provides further information on the question you raised.

https://homeguides.sfgate.com/poisonous-milkweed-humans-74425.html

I am sorry I meant a danger to the Monarchs.

Thanks

There is no danger to monarchs, neither to the adults, to the eggs, nor to the larvae. Being typical arthropods, they do not possess the cardiac system of warm blooded animals. Consequently they are unaffected by the cardiac glycosides.

Here is a site that suggests different types of milkweeds to grow in Minnesota for monarchs:

http://www.thevagary.com/monarch5.pdf

Good Luck!!