Definition
The dahlia is a peony with large stars: instead of many fine points, the shell holds fewer but much bigger stars, often short comets, that spread in thick, very bright rays before dying out. The break looks more open and more “structured” than a peony's, with saturated colours since each star carries a substantial flame. Dahlias are fired from 100 to 300 mm; in small calibres they lose their point because the stars can no longer be told apart. They are often offered with colour change or a crackling tip. Placed in the middle of a volley of peonies, a dahlia brings a contrast of scale; fired alone in a large calibre, it makes a simple, readable highlight.
In practice, for the display company
A dahlia counts as an ordinary shell for stock, mortar and declaration, but carries more weight in the visual composition. PyroDesk files it in its shape taxonomy, and PyroSimulator renders the large stars at their proper size, so you can balance the peony/dahlia alternation of a volley before buying.