Gold Stars for Goldenrod

It’s September and this, my friends, is glorious goldenrod season. These blazing yellow flowers are a visual feast shimmering in the early fall sunlight all around my city, in our many metroparks and nature preserves. But there’s so much more to them than what meets the average human glance. My gosh, this family of plants should be celebrated for so many reasons…where do I start?

Goldenrods and asters at the Toledo Botanical Garden

A bit of an introduction is probably in order first. There are more than 100 known species of goldenrods worldwide (primarily in the genus Solidago) and most of them are in North America. Ohio is home to a couple dozen goldenrods, and I’m happy to say that I’ve got four of them in my own garden (so far).

Ambrosia trifida, aka Giant Ragweed (Le.Loup.Gris/ Wikimedia Commons) – This causes seasonal allergies, not goldenrods!

And let’s clarify something: Goldenrod often gets a bad rap when it’s mistakenly blamed for seasonal allergies. But the pollen of goldenrods is too heavy and sticky to be blown around on the wind, so if you suffer from pollen allergies, you might want to point your finger toward ragweed, which blooms at the same time and throws its pollen around quite recklessly.

By now you know that I always give a plant bonus points if the insects love it, and goldenrods get plenty of gold stars because they are pollinator magnets of the highest caliber. They don’t produce the most nectar, but since they have so many flowers on each plant, that helps maximize feeding opportunities. One source in my library says the average goldenrod plant has more than 1,000 flowers. (Goldenrods of Northeast Ohio, by Bissell, McKee, and Semroc.)

Most of my other garden plants are past their peak now, but thank goodness I’ve got some goldenrods. They’re known to support over 400 species of insects, who use them as food or as host plants for their larvae. If I walk up to my stiff goldenrod, it’s guaranteed to be buzzing with all kinds of bees and wasps. And since they bloom so late in the season, they’re not only important to the bees, moths, and other resident insects, but are essential food sources for migrating monarch butterflies and dragonflies. Of course the dragonflies don’t eat the plants directly, but green darners and wandering gliders often hunt over prey-rich fields of goldenrod late in the season, fueling up for their long journeys.

This is Riddell’s goldenrod (Solidago riddellii), and this is its first year in a new bed in my garden. My friend Kate gave me one plant at the end of last summer, and this is what it looks like today. It’s more than four feet tall and absolutely loaded with native bumble bees every time I look at it.

The other day I was hoping to document some of the bumble bee species. I’ve been lax in learning to identify many of the bees who live in my yard. I know the common eastern bumble bees and their almost-twins the carpenter bees, but there are lots of other smaller bumbles here too. My eyes go crossed every time I think about trying to figure them out. But happily, I found a convenient distraction from that tedious task on this occasion: As I got close to one of my patches of stiff goldenrod, I noticed somebody else in there among the bees.

Ambush bug on stiff goldenrod in my garden

An ambush bug! Normally I see these insect predators sitting motionless waiting for their next victim to happen along, but this one was moving around among the flowers. I started taking video, thinking that he’d settle into his chosen spot and I might see him grab lunch. But it looked like he was feeding on the flowers. Odd. I’ve since learned that, in addition to eating other insects, they also feed on the nectar of flowers. I love those learning moments!

As you’ll see in this two-minute video, there was no insect on the menu this time. This particular branch of the goldenrod was especially busy with activity — you’ll see an eastern bumble bee and a couple small wasps making an appearance as well as the ambush bug. I enjoy sitting at eye level at one of these insect Grand Central stations to imagine what that tiny world might be like.

As I was showing my friend Ginny around the garden the other day, she commented about something smelling nice. We lifted up the stiff goldenrod and inhaled its sweet sweet fragrance. I’m a bit embarrassed to say that I’d not even noticed that fragrance in the two years I’ve had this in my garden. Although I’d certainly noticed the exuberance of those tall, stiff stems that like to snake their way around other plants and weigh them down. I’m still learning how to tame it and teach it some manners so it can play nicely with the other natives, but I’d never stopped to smell it. And now I can’t walk past it without stopping to breathe it in.

Part of my sensory processing sensitivity (SPS) is an extreme reaction to strong fragrances, whether they’re perfumes, candles, or even flowers. For many years I was seduced by the sweet fragrance of hyacinths in the supermarket, and would often bring some home to freshen up my house in the early spring. But once I got them in the house the scent was overpowering and I had to take them outside. So when I find a plant that has a lighter scent like this stiff goldenrod, I can bring it inside and enjoy it in the house. More gold stars!

I brought some goldenrods and asters inside and Sam immediately tried to eat them!

And sticking with the theme of yellow, let’s not forget to include an insect. As I did my dragonfly monitoring route the other day, I walked up to check out the insects on a small patch of unidentified goldenrod beside the lake. I saw something moving around among the flowers, and as I moved in to take a closer look I was intrigued by what I thought was a large wasp. It turned out to be this locust borer (Megacyllene robiniae), a rather large beetle (up to 1″ long) with bold, geometric patterns of yellow on its black body. And this was the first time I’d ever seen this particular insect, so I was even more pleased to meet it.

Locust borer beetle (Megacyllene robiniae)

They lay eggs in the wood of black locust trees, and the adults feed on goldenrods. In fact, the robiniae part of its scientific name comes from the name of the black locust tree, Robinia pseudoacadia. Coincidentally, I had just been looking at a black locust tree before I found the nearby patch of goldenrod, and I’ve read that these beetles can be more abundant in exactly that situation, when goldenrod occurs near their larval host trees. Interesting, no? (Another learning moment for me!) I need to go back there to take a closer look at that area to see if I can find more of these beautiful beetles.

And as we officially award a big gold star to goldenrod, let’s acknowledge how great it is that these gorgeous glowing flowers bloom at the same time as the lovely purple and yellow New England asters. The impact of placing complementary colors together is well known, and there’s real science behind why those combinations are so visually pleasing. All I know is that every time I visit my garden in September I feel a huge smile spreading across my face as my breathing slows and I absorb the colors into my soul, trying to imprint them deeply so I can recall them when everything is brown and gray in a few months.

I’ll leave you with this gallery from my garden, showing just a small portion of the insects who live and love among the purple and gold flowers. Click any image to enter the slideshow with captions. Enjoy! (Note: if you’re using your phone to read this, you won’t see the photo captions unless you click the small “i” in a circle in the bottom corner of your screen.)