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My Calliopsis tinctoria plants performed beautifully this year. I start a few plants from seed in my basement each winter, and I also tuck a few seeds outside once the soil warms in May. The previous year’s plants also give me a handful of surprise volunteers each spring.
Calliopsis seeds are ridiculously cheap (no affiliation) and extremely easy to grow.
The plants grow 24 inches tall in sun or part-sun. I sometimes have to stake the plants that grow in part-shade or they tip in heavy rains or wind. I deadhead them to extend the blooming season, but other than that they need no special care or attention.