Tag Archives: Asclepias incarnata

Help monarch butterflies by giving away milkweed plants

Like most monarch fans, I dutifully pack my yard with milkweed and hope the offering will somehow offset the effects of habitat loss and pesticide applications on population levels. But I’m not a complete idiot so I know that my contribution is probably rather inconsequential. Planting milkweeds for a few dozen monarchs is not really going to help population declines.

So this year I finally got around to something I’ve been meaning to do for years: give away lots of milkweed plants. My goal was to distribute free seedlings to several hundred people in my town (Swarthmore, Pennsylvania), ideally creating a concentration of milkweed that might make a difference. And because milkweeds are perennials and produce seeds that disperse with the wind, all of those initial milkweeds would do their reproductive duties for years, seeding vacant lots and such. Perhaps after a few years we will start seeing flocks of monarchs again (I’m an optimist).

This post summarizes how I grew the plants and gave them away, just in case anyone else might be nudged to do something similar. If one person in every town did this we might reverse the yearly declines in monarch populations.

Step one was to collect seeds. If you’ve never done it before it’s easy — just pick browning pods and let fully dry. Here’s a photograph from 2018 showing some swamp milkweed pods:

You don’t need to, but I decided to clean my seeds. Here’s the end product:

Milkweed seeds germinate best if they are exposed to a period of cold, ideally when moist. So all I did was scatter the seeds on a few large containers (actually, unused litterboxes). Come spring I had hundreds of seedlings emerge.

As seedlings emerged I’d transfer them to small Dixie cups. I soon covered almost every square inch of sunny space in my yard. (That’s my bee hotel, by the way.)

Then I started giving them away to people in town who had expressed an interest in growing milkweed. I put the seedlings into cheap paper cups and then delivered sets of threes to doorsteps. This used up about two dozen seedlings.

To get people to plant milkweed I thought it might be fun to leave pots around town along with, “please adopt us” notes. I gave away probably 100 this way. Usually the pots would be taken within an hour or so. It was fun leaving them in obscure spots around town, and I was hoping to build some curiosity about who was doing this and why.

Here’s the note I left with each set. I went with “rose milkweed” because I worried that “swamp milkweed” might be a turn-off for some. But same plant: Asclepias incarnata, my favorite milkweed. And it’s native.

Here are seedlings bound for one of the giveaway events. There were even more pots in the front.

Here’s my display table. I held the events on days when large crowds would be expected, so probably 95% of takers were people who didn’t realize they even wanted milkweed plants.

In total, I probably gave away 500 milkweed plants this year. I’m not positive it was a success but I think I noticed more monarchs around town this year. As anecdotal evidence, I wasn’t even trying to photograph a monarch when taking this picture:

If you have milkweed plants and seed pods, give it a try in 2020. It would be especially good if garden clubs across the country made this a priority.

Chinese mantids eat monarch butterflies

This post is a PSA for anyone keen on helping monarchs: if you find Chinese mantids (Tenodera sinensis) in your yard, kill them. As proof, below is a photograph of one that had just snagged a monarch visiting my swamp milkweed. The monarch is fine, by the way. After I intervened she flew off, then came back within seconds and resumed ovipositing.

Monarch butterfly captured by a Chinese mantid (Tenodera sinensi

But unless you’re observing your milkweed patch obsessively, you’ll probably never catch a Chinese mantid in the act. But you can infer their presence by piles of monarch wings (i.e., no body attached). No other animal does this to monarchs.

Monarch butterfly wings left by Chinese mantid predation

And caterpillars are just as susceptible. Here’s a Chinese mantid I interrupted just as it was about to strike:

At base of milkweeds was a pile of monarch butterfly wins. Swarthmore, PA.

Chinese mantis can be easily distinguished from any of the native mantids by the presence of a yellow dot in between the forelegs.

Chinese mantis (Tenodera sinensis)

If you find an ootheca (egg case) of this species, crush it. The oothecae have an irregular, messy surface that looks like a blob of brown, poorly-applied insulating foam. Oothecae of the native Carolina mantis are much smoother and streamlined (see, “Identifying mantid egg cases in Pennsylvania“).

First-instar nymph of Chinese mantis (Tenodera sinensis) on ootheca

If you’re like most people (including myself), you grew up believing that mantids are a pesticide-free way of reducing garden pests. How could thousands of web sites be wrong?? The truth is, however, that Chinese mantids are so large that they tend to only eat large insects, and that usually means mainly butterflies, not aphids or other species that are tiny. So if you hate butterflies, by all means encourage Chinese mantids in your yard. But if you like butterflies in your garden, kill the Chinese mantids. And don’t just relocate them, even though that seems like the friendly, eco, green, peace-loving thing to do. Moving introduced, invasive species to another location simply facilitates further spread.

FYI, Chinese mantids also eat hummingbirds, plus other birds that are even bigger. The authors of that linked paper conclude,

“Our compilation suggests that praying mantises frequently prey on hummingbirds in gardens in North America; therefore, we suggest caution in use of large-sized mantids, particularly non-native mantids, in gardens for insect pest control.”

Italics mine.