|Fig. 111: The karanda (Carissa carandas) is small and gummy but yields colorful, tart juice.|
This species is a rank-growing, straggly, woody, climbing shrub, usually growing to 10 or 15 ft (3-5 m) high, sometimes ascending to the tops of tall trees; and rich in white, gummy latex. The branches, numerous and spreading, forming dense masses, are set with sharp thorns, simple or forked, up to 2 in (5 cm) long, in pairs in the axils of the leaves. The leaves are evergreen, opposite, oval or elliptic, 1 to 3 in (2.5-7.5 cm) long; dark-green, leathery, glossy on the upper surface, lighter green and dull on the underside. The fragrant flowers are tubular with 5 hairy lobes which are twisted to the left in the bud instead of to the right as in other species. They are white, often tinged with pink, and borne in terminal clusters of 2 to 12. The fruit, in clusters of 3 to 10, is oblong, broad-ovoid or round, 1/2 to 1 in (1.25-2.5 cm) long; has fairly thin but tough, purplish-red skin turning dark-purple or nearly black when ripe; smooth, glossy; enclosing very acid to fairly sweet, often bitter, juicy, red or pink, juicy pulp, exuding flecks of latex. There may be 2 to 8 small, flat, brown seeds.
Formerly there were believed to be 2 distinct varieties: C. carandas var. amarawith oval, dark-purple, red-fleshed fruits, of acid flavor; and var. dulcisround, maroon, with pink flesh and sweet-subacid flavor. However, David Sturrock, a Florida horticulturist who took a special interest in the karanda, observed these and other variations throughout seedling populations.
|Fig. 112: The karanda, shrubby or climbing, is conspicuous when in starry bloom.|
The karanda is native and common throughout much of India, Burma and Malacca and dry areas of Ceylon; is rather commonly cultivated in these areas as a hedge and for its fruit and the fruit is marketed in villages. It is rare in Malaya except as a potted plant in the north; often grown in Thailand, Cambodia, South Vietnam and in East Africa. It was introduced into Java long ago as a hedge and has run wild around Djakarta. The karanda first fruited in the Philippines in 1915 and P.J. Wester described it in 1918 as "one of the best small fruits introduced into the Philippines within recent years."
The United States Department of Agriculture received seeds from the Middle Egypt Botanic Garden in 1912 (S.P.I. #34364); from P.J. Wester in the Philippines in 1918 (S.P.I. #46636) and again in 1920 (S.P.I. #51005); and a third time in 1925 (S.P.I. #65334). The shrub has been cultivated in a limited way in Florida and California and in some experimental gardens in Trinidad and Puerto Rico.
The karanda is more cold-tolerant than the carissa. It grows from sea-level to 2,000 ft (600 m) in the Philippines; but up to an altitude of 6,000 ft (1,800 m) in the Himalayas. Burkill says it is not really suited to the humid climate of Malaya. Like the carissa, its chief requirement is full exposure to sun.
The plant grows vigorously in Florida on sand or limestone. In India, it grows wild on the poorest and rockiest soils and is grown as a hedge plant in dry, sandy or rocky soils. It is most fruitful on deep, fertile, well-drained soil but if the soil is too wet, there will be excessive vegetative growth and lower fruit production.
Propagation is usually by seed because cuttings have never rooted readily. Experimental work in India has shown that cuttings from mature plants may not root at all; 20% of hardwood cuttings from trimmed hedges have rooted in November but not when planted earlier. Cuttings from nursery stock gave best results: 10% rooted in late September; 20% in early October; 30% in late October; and 50% in early November. In all cases, cuttings were pre-treated with indolebutyric acid at 500 ppm in 50% alcohol. Sturrock found that tender tip cuttings could be rooted under constant mist; also that the karanda can be grafted onto self-seedlings. It has proved to be a good rootstock for carissa.
The plant grows slowly when young. Once well-established, it grows more vigorously and becomes difficult to control. If kept trimmed to encourage new shoots, it will bloom and fruit profusely.
The karanda may bloom and fruit off and on throughout the year. For use unripe, the fruits are harvested from mid-May to mid-July. The main ripening season is August and September. The 5-pointed calyx remains attached to the plant when the fruit is picked, leaving a gummy aperture at the base.
Freshly-picked ripe fruits can be kept at room temperature only 3 or 4 days before they begin to shrivel.
Pests and Diseases
Nursery plants are probably prone to the same pests that attack young carissas.
Fungus diseases recorded on the karanda in Florida are algal leaf spot and green scurf caused by Cephaleuros virescens; twig dieback from Diplodia natalensis; and stem canker induced by Dithiorella sp.
The sweeter types may be eaten raw out-of-hand but the more acid ones are best stewed with plenty of sugar. Even so, the skin may be found tough and slightly bitter. The fruit exudes much gummy latex when being cooked but the rich-red juice becomes clear and is much used in cold beverages. The sirup has been successfully utilized on a small scale by at least one soda-fountain operator in Florida. In Asia, the ripe fruits are utilized in curries, tarts, puddings and chutney. When only slightly underripe, they are made into jelly. Green, sour fruits are made into pickles in India. With skin and seeds removed and seasoned with sugar and cloves, they have been popular as a substitute for apple in tarts. British residents in India undoubtedly favored the karanda as being reminiscent of gooseberries.
Analyses made in India and the Philippines show the following values for the ripe karanda: calories, 338 to 342/lb (745-753/kg); moisture, 83.17-83.24%; protein, 0.39-0.66%; fat, 2.57-4.63%; carbohydrate, 0.51-0.94%; sugar, 7.35-11.58%; fiber, 0.62-1.81%; ash, 0.66-0.78 %. Ascorbic acid content has been reported as 9 to 11 mg per 100 g.
Fruit: The fruits have been employed as agents in tanning and dyeing.
Leaves: Karanda leaves have furnished fodder for the tussar silkworm.
Root: A paste of the pounded roots serves as a fly repellent.
Wood: The white or yellow wood is hard, smooth and useful for fashioning spoons, combs, household utensils and miscellaneous products of turnery. It is sometimes burned as fuel.
Medicinal Uses: The unripe fruit is used medicinally as an astringent. The ripe fruit is taken as an antiscorbutic and remedy for biliousness. The leaf decoction is valued in cases of intermittent fever, diarrhea, oral inflammation and earache. The root is employed as a bitter stomachic and vermifuge and it is an ingredient in a remedy for itches. The roots contain salycylic acid and cardiac glycosides causing a slight decrease in blood pressure. Also reported are carissone; the D-glycoside of B-sitosterol; glucosides of odoroside H; carindone, a terpenoid; lupeol; ursolic acid and its methyl ester; also carinol, a phenolic lignan. Bark, leaves and fruit contain an unnamed alkaloid.