Diospyros virginiana In respect to the power of making heartwood, the persimmon rarely develops any heartwood until it is nearly one hundred years old. This heartwood is extremely close-grained and almost black, resembling ebony (of which it is a true variety). It is a common misconception persimmon fruit needs frost to ripen and soften, called bletting. Some, such as the early-ripening varieties "pieper" and "NC21"(also known as "supersweet"), easily lose astringency and become completely free of it when slightly soft at the touch—these are then very sweet, even in the British climate. On the other hand, some varieties (like the very large
Diospyros "Zeus's wheat" but more generally intends "divine food" or "divine fruit". Muddled translations sometimes give rise to curious and inappropriate interpretations such as "God's pear" and "Jove's fire". The genus is a large one and the number of species has been estimated variously, depending on the date of the source. The Royal Botanic Gardens, Kew, list has over 1000 entries, including synonyms and items of low confidence. Over 700 species are marked as being assigned with high confidence. The leaves of "Diospyros blancoi" have been shown to contain isoarborinol methyl ether (also called cylindrin) and fatty esters of α- and