The Case of the Mistakenly Labeled Lobelias
I love Cardinal Flowers (Lobelia cardinalis), but they don’t love me. Which is to say, they always die on me after a couple of years. They’re fairly finicky. They like lots of sun, lots of moisture, and bed sheets with a thread count of at least 1,800.
But that color! Plus hummingbirds love them – in fact, they are one of few North American plants actually pollinated by hummingbirds – and you can never do enough for hummingbirds.
And Judy missed them, too.
So finally I said to myself, what the heck. I’ll just buy some, and if they die, I’ll replace them. They don’t cost much more than annuals bought as plants.
So I bought a bunch. I planted them in front of our south-facing back porch, near a drainpipe. I also put some in containers.
However, when my Lobelias started to bloom, it became apparent that only one of them was actually a Cardinal Flower. All the rest of them were Great Blue Lobelias (Lobelia syphillitica).
Great Blue Lobelias are very nice plants. They’re not as finicky Cardinal Flowers. But I wanted Cardinal Flowers.
I considered returning them to the garden center where I had bought them. However, I couldn’t remember where I’d bought them – it was one of the two garden centers where I make almost all my (offline) plant purchases, but which one? And of course I hadn’t remembered to keep the receipt.
So I guess I have decided to make the best of having a bunch of Great Blue Lobelias, with occasional outbursts of pointless grumbling.
On a sort of related point: both L. cardinalis and L. siphilitica are native to the American Midwest. However, I think most of the Lobelias sold in garden centers are hybrid cultivars. It turns out this is one instance where the straight species really are a much better choice for pollinators.
As I mentioned before, L. cardinalis is pollinated by hummingbirds. It has evolved to provide a large quantity of nectar to meet the high energy needs of its pollinator.
L. siphilitica is pollinated by bumblebees. They need a lot less nectar, and so L. siphilitica provides a great deal less than Cardinal Flower.
Lobelia cultivars are often L. x intermedia hybrids. They attract hummingbirds with a shape and color that is similar to Cardinal Flower. However, because of their L. siphilitica parentage, they do not offer the same reward in food energy, which is kind of a dirty trick on the hummingbirds, who consume calories by the boatload every minute that they’re in the air.
So be kind to hummingbirds: if you can’t plant Cardinal Flower, don’t plant the hybrid Lobelia cultivars.
FUN FACT: Lobelia siphilitica got its specific name because, yes, for some misguided reason it was used to treat syphilis.
That’s all for now.