Symphyotrichum puniceum, Purple-Stemmed Aster or Swamp Aster

While Purple-Stemmed Aster is their official common name in the VASCAN database, for the populations in the Perth area I think that one of their other common names of Swamp Aster is more descriptive; the purple on their stems is, at most, a small patch or streak at their leaf and stem joints, but they do consistently make their homes in areas that are very wet, or even under water, in the spring.

By whatever name, these, like a lot of the Aster family, put on an incredible show of blooms in the fall of 2023. There are several large patches that I noted occupying space in roadside drainage ditches, resisting the advancement of invasive European strains of Reed Canary grass that have filled a lot of sunny, seasonally wet areas with near monocultures of wide, green grass blades in this part of the privince. (Once you learn to spot this grass, it is rather jarring to see just how many spaces these have filled. They don’t get as much attention as the tall, fluffy Phragmites but I suspect that they occupy a similar amount of wetland area around Ottawa and Perth.)

A paler shade of purple or lavender than New England Aster, Purple-Stemmed Asters bloom at roughly the same time and have a similar overall appearance. The ones in their preferred sunny and seasonally wet settings grow to 3’ to 4’ tall. There are a few babies from seeds I received in 2022 tucked into a dry-ish nursery bed that grew to around 12” tall last summer and, despite their reduced stature and less than ideal setting went ahead and bloomed anyway. I suspect that, even in a dry setting, they will get taller as they mature but I wouldn’t be surprised if they only grow to a couple of feet in height with the limited moisture availability. I’ll probably move them to another spot that is quite a bit wetter next spring.

If you are planning a pollinator garden for a wet setting like a rain garden, a drainage ditch or a spot in your yard where the spring melt tends to make long lasting puddles, I’d recommend considering this species, along with Pink Swamp Milkweed, Canada Bluejoint Grass, Brown Fox Sedge, Flat-Topped White Aster, Common Boneset, Joe-Pye Weed, Swamp Rosemallow, American St. John’s Wort, Cardinal Flower, Great Blue Lobelia, Fringed and Winged Loosestrife, Allegheny Monkeyflower, Scarlet Beebalm, Giant Goldenrod, Wrinkleleaf Goldenrod, Tall Meadowrue, Blue Vervain, Wingstem and Tall Ironweed. You’d end up with the prettiest drainage ditch in your neighbourhood 😊.