Received August 31, 2020. Parentage unknown. First bloomed 1980’s, first propagated 2015. Has been distributed under this name to a number of botanical gardens in Europe. The name and description have also been previously published in Index Plantarum of Pruhonice Botanic Garden. Midseason bloom (early in the Lactiflora season). Very dark red SINGLE (RHS:61A). Three to four blooms per stem, 7¼ inches in size (18½ cm). Two to three rows of guard petals, somewhat cupped, variably notched, average width 2½ inches (5.7 cm). Usually 5 carpels, smooth, reddish purple (RHS:59A). Stigmas normal anatomy, same color as carpels. Pollen-bearing stamens with filaments orange-red at the base, yellow at the top. Fertile. Fragrant. Foliage emerges dark purple. Leaves become dark green with purple veins and often with a purplish bronze wash. Stems, petioles, and buds are purple at flowering. Upright growth to 35½ inches (90 cm). Troja is a city district of the capital city of Prague in which the Prague Botanical Garden is located. Other plants introduced from the Botancal Garden were given the prefix “Trojan” to indicate their origin here. This name comtinues that tradition, and “Black” of course, refers to the very dark flower and stems of this peony.