Queen Anne’s Thistle: A Rare Non-Native Perennial Worth Knowing About
If you’ve stumbled across the name Queen Anne’s thistle (Cirsium canum), you’re likely dealing with one of the more mysterious members of the thistle family. This perennial forb has a rather limited presence in North American gardens, and for good reason – it’s quite the enigma in the plant world.
What Exactly Is Queen Anne’s Thistle?
Queen Anne’s thistle is a non-native perennial that belongs to the vast Cirsium genus, which includes hundreds of thistle species worldwide. Like its thistle cousins, this plant is classified as a forb – essentially a soft-stemmed plant that lacks the woody tissue you’d find in shrubs or trees. Think of it as the herbaceous cousin in a family full of prickly personalities.
As a perennial, this plant comes back year after year, though its exact appearance and growth habits remain somewhat of a mystery due to limited documentation and research.
Where Does It Grow?
Here’s where things get particularly interesting (and a bit puzzling). Queen Anne’s thistle has been documented in Massachusetts, making it one of the more geographically restricted non-native plants you’ll encounter. Its limited distribution suggests it hasn’t become widely established across the United States like some of its more aggressive thistle relatives.
Should You Plant Queen Anne’s Thistle?
This is where we need to have an honest conversation. While Queen Anne’s thistle isn’t currently flagged as invasive or noxious, its non-native status and the general reputation of thistles for spreading aggressively give us pause. Plus, with so little information available about its specific growing requirements, wildlife benefits, and long-term behavior in gardens, it’s a bit of a wild card.
Better Native Alternatives
Instead of gambling with Queen Anne’s thistle, why not consider some fantastic native alternatives that offer similar spiky charm but with well-documented benefits?
- Field thistle (Cirsium discolor) – A native beauty with purple flowers that butterflies absolutely adore
- Tall thistle (Cirsium altissimum) – Lives up to its name and provides excellent wildlife habitat
- Swamp thistle (Cirsium muticum) – Perfect for wetter areas and less aggressive than many thistle species
If You’re Determined to Grow Thistles
Should you decide to work with any thistle species, here are some general guidelines that would likely apply to Queen Anne’s thistle as well:
- Location: Full sun to partial shade
- Soil: Most thistles are surprisingly adaptable to various soil conditions
- Hardiness: Based on its Massachusetts presence, likely hardy in USDA zones 3-8
- Maintenance: Deadhead flowers before they go to seed to prevent unwanted spreading
- Spacing: Give them room – thistles don’t like to be crowded
The Bottom Line
Queen Anne’s thistle remains something of a botanical puzzle – a non-native perennial with limited distribution and even more limited information. While it’s not necessarily problematic, the uncertainty around its behavior and the abundance of well-documented native alternatives make it hard to recommend enthusiastically.
If you’re drawn to the architectural beauty and wildlife benefits that thistles can provide, stick with native species that come with a track record of playing nicely in North American ecosystems. Your local butterflies, birds, and beneficial insects will thank you for choosing plants they’ve evolved alongside for thousands of years.
Sometimes the most interesting plants are the ones we admire from afar rather than invite into our gardens – and Queen Anne’s thistle might just be one of those fascinating botanical mysteries better left to specialized collectors and researchers.
