Justicia californica

Chuparosa is Spanish for hummingbird, and the plant is named for what visits it.

It matters most because of when it blooms. Chuparosa flowers from late fall through spring, filling the stretch when almost nothing else in the low desert is producing nectar. Costa's hummingbird — the small desert species with the flared purple gorget that sweeps back past the throat like a mustache — breeds earlier than any other Arizona hummingbird, starting as early as February. That timing only works because chuparosa and ocotillo are already open.

Anna's and black-chinned hummingbirds work it too, along with verdins, which cheat by piercing the base of the tube and taking nectar without touching the pollen.

The flowers are edible and taste faintly of cucumber. Worth knowing, mildly disappointing.

It's a loose sprawling shrub, thin on leaves, and it looks like nothing much in a nursery pot. Planted where it gets some reflected warmth against a south wall, it will be the most-visited thing in the yard from December to April.