By Emma Murphy, Master Gardener
Last year around this time I wrote a blog about reclaiming a garden bed from the dreaded ditch lily (Hemerocallis fulva), now considered an invasive species by many organizations including Ontario Parks and the US Fish & Wildlife Service and the U. S. National Park Service. If you’ve ever struggled with this plant you know what I mean.
The other plant growing in our large Lakefield garden when we moved in (more than 20 years ago) is what I was told was called an ‘outhouse plant‘. I eventually learned that the Latin name for this plant (also called golden glow or tall coneflower) was Rudbeckia laciniata “Hortensia”.
It’s a cultivar of our native Rudbeckia laciniata, also known as Cut Leaf Coneflower or Green Headed Coneflower, which has a lovely simple daisylike flower (whereas the Hortesia cultivar is a double ‘puffy’ flower).
The outhouse plant was pleasant enough so I let them grow for years in what I call our ‘back 40’, meaning our naturalized garden area at the back of the property, behind the cedar rail fence. Yes they were tall and gangly, and fell over in thunderstorms. Yes they spread, but they gave the prolific Canada Goldenrod (Solidago canadensis) and New England Asters (Symphyotrichum novae-angliae) a run for their money in August/September. And hey, I had more than enough to deal with in the rest of my more organized garden!
However, as I started to learn more about both native (and invasive) plants over the years I realized that I might have a problem. The outhouse plant isn’t a huge problem per se, as it can be controlled through digging, Chelsea chop etc., but its double shape means that it offers minimal benefit as food for our pollinators. And I wanted plants that not only look beautiful but have an ecological benefit. So I sat in my hammock and pondered.
As a result of winter sowing (first time this past winter – highly recommend!) I have lots of new native plant seedlings, including some of the ones I featured in my May blog – A Few of My Favourite Native Plants – Culver’s Root (Veronicastrum Virginicum), Cardinal Flower (Lobelia cardinalis), and Green Headed Coneflower (Rudbeckia laciniata). I certainly have lots of the native Rudbeckia, as well as Boneset (Eupatorium perfoliatum), Giant Ironweed (Vernonia gigantea), and Purple Giant Hyssop (Agastache scrophulariifolia).
So the clearing of the outhouse plant began in earnest last week, and by the end of two afternoons I had an area to work with.
Definitely not light work, but not too difficult either compared to other plants. The area is now clear, and I’ll be putting in Green Headed Coneflower (the native), Boneset, Giant Ironweed, and Purple Giant Hyssop. They can all tolerate a little competition (a good thing for native plants, especially tall ones) and basic soils.
If I have space I might even mix in some shorter plants like native Bush honeysuckle (Diervilla lonicera) and Pearly Everlasting (Anaphalis margaritacea) in at the front as they can tolerate dry conditions. The area is mostly sunny all day. Unfortunately my beloved Cardinal Flower and Turtlehead are too dry for this location.
We’ll see how this experiment works and check back in with you all on another blog. If it works we’ll expand into another area of outhouse plant that I recently cut down, but haven’t removed yet…a work in progress. There are only so many hours in my (still working part time) day. And I still need to get that Canada Ggoldenrod under control…but that’s another story…