There are several varieties in cultivation, varying in the degree of hardihood, time of ripening, thickness of shell, size and other particulars.
From its hardihood the plum is one of the most valuable fruit trees, as it is not particular as to soil, and the crop is less likely to be destroyed by spring frosts.
For currants and raisins, both produced by varieties of the grape-vine, see the respective articles.] Apart from their economic value, vines are often cultivated for purely ornamental purposes, owing to the elegance of their foliage, the rich coloration they assume, the shade they afford, and their hardihood.
Its pure white or rose-red blossoms, heralding the first approach of genial weather, are regarded with special favor and are accounted the symbol of unassuming hardihood.
Already in the 7th century B.C., when Hellenism was still in a rudimentary stage, the citizens of the Greek city-states had been known to the courts of Babylon and Egypt as admirable soldiers, combining hardihood with discipline, and Greek mercenaries came to be in request throughout the Nearer East.