Sour cherry, rootstock
Prunus mahaleb, Hardiness : Zone 3
Height X Width
Edible parts description
American cherries, tart and soft
Harvest : Begins in mid-july
Sun exposure
Soil type
Edible parts
Self-fertile, good pollinator
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Description, from Wikipedia

The tree's bark is grey-brown, with conspicuous lenticels on young stems, and shallowly fissured on old trunks. The leaves are 1.5–5 centimetres (12–2 inches) long, 1–4 cm. wide, alternate, clustered at the end of alternately arranged twigs, ovate to cordate, pointed, have serrate edges, longitudinal venation and are glabrous and green. The petiole is 5–20 millimetres long, and may or may not have two glands. The flowers are fragrant, pure white, small, 8–20 mm diameter, with an 8–15 mm pedicel; they are arranged 3–10 together on a 3–4 cm long raceme. The flower pollination is mainly by bees. The fruit is a small thin-fleshed cherry-like drupe 8–10 mm in diameter, green at first, turning red then dark purple to black when mature, with a very bitter flavour; flowering is in mid spring with the fruit ripening in mid to late summer.

It demonstrates selective fruit abortion, producing a high proportion of excess flowers that result in low fruit set levels. This reduces the number of "poor quality" fruit and increases the viability of its seeds.