I have had a nice, dense clump of this plant for 3 years and I love it. Interesting flower buds that have a "netted or fish-net" appearance. Striking blue-purple unique flowers, sort of like a bee balm but more airy. Invasive is not a problem for me. In fact, I would like more of this to transplant and this is the first year I have new plants coming up away from the original clump.
At horticultural club plant sales, there are, invariably, clumps of Centaurea montana offered by [in my opinion, unkind] members. It grows rapidly through the garden on rhizomes, and seeds prolifically as well. I have always included it in an 'Invasives' section when I have managed plant sales, in fairness to new gardeners.
This is one of my favorite plants! It grows wonderfully in a partially shaded spot along the edge of the woods in my garden. It has the perfect bloom time for zone 4 in NH. Centaurea Montana shines just after the spring flowers fade but before the summer show begins. It fills in the color gap wonderfully.
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