Few plants cause greater anxiety in sophisticated American gardener's hearts than the blue poppies: they hate temperatures much above 70F and of course, most of the USA is quite steamy in the summer months. But there is one plant that not only seems to tolerate warmer conditions, it has proved perennial and self sows at Raven Ranch, the remarkable home and garden of Bob and Rebecca Skowron--keen rock gardeners who live near Denver.
Standing back a bit......
I put the feeble "affinity" in the middle of the Latin name because the REAL M. horridula is supposed to be monocarpic (blooms and dies). Rebecca assures me hers do not bloom and die, so I'm not sure what to call the plants. She has them planted under pondersa pines in a rather distant part of her garden where I know she can't hover over them and fuss. Douglas county (where they live) is almost 1500 ft. higher in elevation than Denver, and daytime temperatures are much cooler most of the time. But they can get 90F on occasion--and this meconopsis obviously doesn't mind.
This shows the setting where they grow and self-sow. I begged her to save seed so we can try this in Denver as well: it would be a great day if we had a true blue meconopsis that was perennial AND self sowed! One can dream can't one?