And making a difference
A “weed” is in the eye of the beholder, says naturalist Jeff Ormiston of Allen County Parks. This assertion jibes with one of the first things we learned in my Master Gardener class – that a weed is simply a plant that is in a place where you do not want it to be.
So weeds get cut back along roadsides or eliminated with herbicide to make way for housing developments, strip malls or just more formal garden beds. The problem for monarch butterflies is that they live on milkweed alone. The growth of herbicide-based agriculture in the Midwest, deforestation in Mexico where they overwinter, severe weather and climate change have all been cited as causes for monarch butterflies’ declining numbers.
Both butterflies and caterpillars feed on milkweed, which contains a bitter chemical that helps protect them from predators. The early bird that gets one of these “worms” gets a nasty surprise with the first taste and decides to hit up some other buffet.
That chemical is cardiac glycoside, which has been used to treat heart disease, according to a 2008 article by Purdue University entomology professor Tom Turpin. Milkweeds are part of the plant genus Asklepias, named after the Greek god of medicine and healing.
Having fewer milkweed plants available to feed on is a major factor in the monarch butterfly’s declining population. So when I saw that Ormiston was giving a talk on how to grow milkweed, I took the opportunity to learn how to add it to the ever-evolving wildflower gallery out back.
There are about 110 milkweed species. Of course you have your common milkweed, but there are a few other possibilities:
Sullivant’s or prairie milkweed grows best in sandy, loamy or rocky soils. This doesn’t grow as aggressively as common milkweed, Ormiston said, so it’s better for smaller areas.
Swamp milkweed, as the name implies, grows along banks, flood plains and other wet areas. Butterfly milkweed is actually a popular landscaping plant with bright orange flowers.
Ormiston and biologist Kate Sanders discussed two more varieties that merit caution. Tropical milkweed has beautiful red and yellow flowers, but there are questions around whether it helps or harms monarch butterflies. Dogbane is not a milkweed variety at all – monarchs can’t survive on it – but it’s often mistaken for milkweed. Milkweed plants are available from Riverview Nursery at local markets; visit www.riverviewnativenursery.com.
You can collect milkweed seed pods just about anywhere. Heartland Restoration Services, Inc. of Fort Wayne and Spence Restoration Nursery in Muncie both sell milkweed seed, but with large minimum orders. Prairie Moon Nursery in Minnesota and Prairie Nursery in Wisconsin were both cited as good sources for smaller quantities.
For planting, there are two ways you can go: The first lets Mother Nature do the work for you, Ormiston and Sanders said. Basically, you disperse the seed just before an inch or two of snow is due to fall (an inexact science, to be sure). Then you walk over the area to make sure those seeds are well acquainted with the soil in which they are to germinate. The plants come up in the spring.
Alternatively, in spring or summer, you can heat some water to 110 to 120 degrees (a little hotter than bath water, Sanders said), pour it over the seeds and let them soak overnight. In the morning, pour off the water and surface-sow the seeds outdoors or in pots next to a window to transplant later.
The presenters were kind enough to distribute some milkweed seeds; see Our Habitat Garden (www.ourhabitatgarden.org/creatures/milkweed-growing.html) for more information on preparing seeds for planting. As of this writing, I have not sown mine – I’m still waiting for that snowfall.
A problem like the declining monarch population may seem too big for one gardener to make a difference, but you know what they say about the butterfly effect.
First appeared in the December 2015 issue of Fort Wayne Magazine.