Few plants have generated as much longing as Meconopsis betonicifolium, the Blue Himalayan Poppy. Its flowers are a blue so pure and saturated they look almost implausible on a summer border — the kind of color that stops visitors mid-sentence. Native to the alpine meadows of Tibet and western China, it evolved in conditions most temperate gardens cannot convincingly replicate: cool, moist summers, perfectly drained but never dry soil, and winters cold enough to force dormancy without being cruel about it.

This is not a plant for humid southeastern summers or warm coastal winters. It thrives in the Pacific Northwest and at elevation, and in those fortunate gardens it will reseed itself quietly and return each year with minimal fuss. Where conditions are marginal, it tends to bloom itself to death after one spectacular season. Give it dappled light or a north-facing slope, keep the soil rich and reliably moist, and resist the urge to let it dry out between waterings. The reward, when it comes, is genuinely unlike anything else in bloom.