pronounced: dy-oh-SPY-ross NY-gruh
pronounced: dy-oh-SPY-ross dy-GY-nuh
Diospyros is from two Greek words, Διος (Dios), of Zeus, and πυρος (pyros), wheat – God’s wheat; but the word διοσπιρος (diospyros) was a name used by the ancient Greeks for the Lithospermum family of plants, gromwell; nigra is from the Latin niger, black, and digyna is from two Greek words, δι-, δια (di, dia), two, and γυνη (gyné), a woman, referring to two carpels.
This is a tropical fruit tree native to eastern Mexico, the Caribbean, Central America, and into Colombia. The young tree photographed is growing in the garden of exotic fruit species at Magnetic Island State School.
The tree is dioecious, so that both male and female trees are needed to produce fruit. The female trees sometimes have some male flowers as well, mostly self-incompatible. Female trees have been known to produce seedless fruits in the absence of a male tree, and on rare occasions have produced fruits with fertile seeds.
It is evergreen, and can grow up to more than 25 m high, with a bole up to 45 cm in diameter. although it is more often found about 6 m in height. The leaves are oblong-elliptic, tapered at both ends, dark green, glossy, and measuring 10 -30 cm long. The flowers, borne on the new shoots, are small and white.
Fruiting usually takes 3 – 4 years when grown from seed, and the trees bear prolifically. The fruits are tomato-like, and measure 4 – 10 cm in diameter, with an inedible skim that turns from olive to a deep yellow-green when ripe, and a pulp which is white and inedible until it ripens, when it assumes a colour, texture and flavour similar to chocolate pudding. The texture is rather like that of a pawpaw. There are usually seeds, up to a maximum of 12.
The fruit is low in fat, and contains about 4 times as much Vitamin C as orange. It is usually picked when hard and allowed to soften and go brown, which it does in 3 – 6 days. It is ripe when a gentle press with the thumb leaves an indent. Ripening usually occurs very suddenly.
The black mushy flesh is rather revolting in appearance (I have seen it likened to axle-grease!), but it is delicious eaten fresh or used as a chocolate substitute in recipes and milkshakes. It can be cut in halves and covered in passion fruit, or the pulp mixed with yoghurt and lemon juice. In Mexico the pulp is mashed with orange juice or brandy and served with cream, or sometimes mixed with wine, cinnamon and sugar.
Unripe fruits are astringent, caustic, bitter and irritating. Some peoples use them as a fish poison.
The tree is frost sensitive, but can tolerate flight frost.
Propagation is usually from seed, which can remain viable for up to several months, but air-layering and budding are also used.
The trees seem to do best at altitudes below 600 m, but they are nor particular about soil. They are sensitive to drought, and require irrigating in dry areas, but are fairly tolerant of flooding. Many varieties and cultivars have been developed, including some seedless ones.
The timber is yellowish to deep yellow with black markings near the heart of old trunks. It is compact and suitable for cabinet work, but seems to be little used.