'Robustissima' might strike fear into the minds of many gardeners, who should take it at its word. If unable to resist its questionable worthiness, it would be prudent to rush out and buy a property of at least an acre in which to place this treasure - preferably in a far, rough corner. I have grown it, but I had lots of land; it's probably not worth the effort.
Have grown this ~4 yrs.in full sun, clay soil. Blossoms late summer/fall, pretty, airy look, pink blossoms on tall (4-5' plants). Spreads by rhizomes and can become invasive in small gardens. Difficult to contain in small area.
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