Verrone's Obsidian

Verrone's Obsidian came from the Verrone breeding program in 2011 and has built one of the most devoted cult followings of any modern dahlia. It is the avant-garde designer's flower: a black star with a silver lining on the petal reverse, closer to jewelry than to a garden bloom. It sells out at Goldenrod Gardens, the Cincinnati Dahlia Society sale, and Misfit Dahlias, and dahlia society plant sales tend to hold it back for members, which tells you who values it most. For moody, sculptural work where a softer flower would look ordinary, this is the stem that finishes the piece.

This is an orchid form, a single ring of rolled, pointed petals around an open center, so it grows and behaves differently from the doubles on this list. Plants run around 3 feet per Gardenia. Open-centered dahlias are pollinator magnets, which means blooms move past their prime faster than doubles; cut just as the stars open fully and deadhead relentlessly to keep the show going. The silver reverse does its best work in arrangements where stems can twist and catch light. There is no honest substitute in this catalog; nothing else here is an orchid form in near-black, which is exactly why it sells out.