Prunus × cistena
Prunus" × "cistena, the purple leaf sand cherry or dwarf red-leaf plum, is a hybrid species of "Prunus", the result of a cross between "Prunus cerasifera" (cherry plum or myrobalan plum) and "Prunus pumila" (sand cherry). A leggy bush or shrubby tree, it typically reaches a height of 1.5–2.5 meters and has a useful life of 10–20 years. The fruits are edible, if strong-tasting. Some people make jams or preserves from them. It is not advisable to eat the pits. Frost-tolerant, purple leaf sand cherries can be grown up to USDA Hardiness Zone 2a . Commercial specimens are typically grafted to a rootstock from any of a number of other species, which will influence their growth form and final height. There are also a limited selection of cultivars available. "Prunus" × "cistena" was developed by Niels Ebbesen Hansen in 1910. In 1993 it won the Royal Horticultural Society's Award of Garden Merit.