Common Yarrow (Achillea millefolium var. megacephala): A Rare Prairie Treasure
If you’re a gardener who loves discovering hidden gems in the native plant world, you might be intrigued by Achillea millefolium var. megacephala, commonly known as common yarrow. But before you rush to add this variety to your wishlist, there’s something important you should know about this particular prairie dweller.
What Makes This Yarrow Special?
This variety of common yarrow is a perennial forb—basically a non-woody flowering plant that comes back year after year. Unlike trees or shrubs, it doesn’t develop thick, woody stems, making it a perfect addition to herbaceous borders and wildflower gardens. As a member of the yarrow family, it likely shares the characteristic feathery foliage and clustered flowers that make yarrows so beloved by gardeners.
Native Range and Rarity Concerns
Achillea millefolium var. megacephala calls the northern reaches of North America home, specifically Saskatchewan and the Northwest Territories in Canada. This hardy plant has adapted to some pretty tough growing conditions in these northern landscapes.
However, here’s where things get serious: this variety has a Global Conservation Status of S5T1, indicating it’s quite rare. If you’re considering adding this plant to your garden, it’s absolutely crucial that you source it responsibly from reputable native plant nurseries that propagate their own stock rather than wild-collect.
Should You Grow This Variety?
The short answer is: maybe, but with caution. Here’s what to consider:
- This is a genuinely native plant that supports local ecosystems
- It’s adapted to harsh northern climates, making it potentially very hardy
- Its rarity means you’d be helping preserve a unique genetic variety
- However, finding responsibly sourced plants may be challenging
Growing Conditions and Care
While specific growing information for this variety is limited, yarrows in general are famously tough customers. They typically prefer:
- Full sun exposure
- Well-draining soils
- Minimal water once established
- Poor to average soil fertility (they actually prefer lean conditions)
Given its native range in Saskatchewan and the Northwest Territories, this variety is likely extremely cold-hardy and adapted to prairie conditions with harsh winters and dry summers.
Garden Design Possibilities
If you do manage to source this rare variety responsibly, it would make an excellent addition to:
- Native plant gardens focused on Canadian prairie species
- Rock gardens or other low-maintenance landscapes
- Naturalized areas where it can spread and establish
- Collections of rare or unusual native plants
The Bottom Line
Achillea millefolium var. megacephala represents something special in the native plant world—a rare variety adapted to specific northern conditions. While it could be a fascinating addition to the right garden, its rarity means it’s not a casual choice. If you’re drawn to this plant, make sure you’re committed to sourcing it ethically and giving it the proper growing conditions it needs to thrive.
For most gardeners interested in yarrow, consider starting with more readily available native yarrow species or varieties that are better documented and easier to source responsibly. But if you’re a serious native plant enthusiast with access to ethical sources, this rare variety could be a meaningful addition to your collection.
