A green flower, which is a rare thing and the reason florists pay attention. Large semi-double blooms open a zingy chartreuse-lime and mature to a soft jade, so a planting carries several shades of green at once. It holds an RHS Award of Garden Merit.
Green does a job no colour can. It provides the visual rest that lets everything else read clearly, and three stems of this through a bunch of hot zinnias and cosmos turns a jumble into an arrangement. That is the whole argument for growing it.
Zinnias want heat and hate cold wet soil, so sow individually, pinch at 10 to 15cm for a bushy plant, and plant out in June rather than May. Water at the base and never over the leaves, because mildew is the one real problem they get.
There is a trick worth knowing before you cut. Shake the stem gently about 30cm below the head. If the flower wobbles, the stem is not mature and it will collapse in the vase within hours. Wait two or three days and try again. A stem that passes holds ten days to a fortnight.
