This section is from the book "The Standard Cyclopedia Of Horticulture Vol2", by L. H. Bailey. See also: Western Garden Book: More than 8,000 Plants - The Right Plants for Your Climate - Tips from Western Garden Experts.
(a geographical name). Papayaceae. Papaya. Small, rapid - growing, un-branched trees, commonly grown in greenhouses as foliage plants and often bearing fruit under such conditions. Juice milky.
Leaves large, soft, long-stalked, in clusters at the top of the trunk: usually dioecious, the male flowers on long axillary peduncles, funnel-shaped, with 10 anthers in the throat, the pistillate flowers larger and with 5 distinct petals and a single pistil with 5-rayed stigma, sessile in the axils of the leaves -Perhaps 20 species, all native to the American tropics, but C. Papaya is cultivated throughout the tropics for its delicious edible fruits. See Papaya.
The soil most suited for caricas is a rich loam, having perfect drainage. As the stem is succulent and tender, great care is necessary to avoid bruising, hence pot-grown plants are much to be preferred to seedlings from the open ground. Seeds should be selected from the best and largest fruits and sown in a well-worked bed under a slight shade. If seeds are quite dry or old, they should be soaked in warm water before sowing. The seedling plants are delicate, and require close watching at first to avoid damping-off. As soon as plants are well up remove the shading, and after the third leaf appears they may be pricked out into a larger bed, or better, potted off in fairly rich soil. After plants are a few weeks old, and have been shifted once into larger pots, they may be set permanently outdoors in the tropics. Caricas seldom branch, but usually grow upright like a palm, hence cuttings are not often available. Sometimes small branches form, and these may be cut off and as readily rooted as most tropical decorative plants, provided the cutting is not too young and tender.
This method has been found in Florida to be too slow, and what is evidently a better method of propagation, by means of graftage, has been devised by Edward Simmonds, of the Plant Introduction Field Station, Miami, Florida. Numerous shoots are formed by the buds at the leaf-scars when a papaya tree is topped, as many as fifty or more being produced. "One of these shoots is taken when a few inches long and about the diameter of a lead pencil, is sharpened to a wedge point, the leaf surface reduced, and inserted in a cleft in a young seedling which has been decapitated when 5 to 10 inches high, and split with an unusually sharp, thin grafting-knife. At this age the trunk of the young seedling has not yet formed the hollow space in the center. Seeds planted in the greenhouse in February produce young seedlings large enough to graft some time in March; these grafted trees, which can be grown in pots, when set out in the open ground in May or the latter part of April, make an astonishing growth and come into bearing in November or December; they continue bearing throughout the following spring and summer, and if it is advisable, can be left to bear fruit into the following autumn." Varieties of superior flavor and better size and shape for shipping, as well as hermaphrodite varieties, may now be successfully maintained.
For complete description of this method see "The Grafted Papaya as an Annual Fruit Tree," by David Fair-child and Edward Simmonds, Circular No. 119, Bureau of Plant Industry, 1913. In temperate climates, caricas have been found to be good decorative plants for both conservatory and summer bedding, the deeply cut, palmate leaves forming a striking contrast to ordinary vegetation. In bedding out, select open, sunny exposure, with perfect drainage, and make the soil rich and friable. Constant cultivation with a fight hoe will cause a luxuriant growth under these conditions, and the planter will be amply repaid for his trouble by beautiful showy specimens as tropical-appearing as palms.
Papaya. Pawpaw. The commonest species in cultivation, sometimes growing to a height of 20 ft., with large palmately 7-lobed leaves, sometimes 2 ft. across, and fruit shaped like a roughly angled melon up to 12 in. long and half as thick, hanging, especially from the lower axils of the pistillate plant. B.M. 2898-9. - From the fruits, which vary in size up to 15 lbs. and in number to the tree from 20-50, is extracted the papaya juice, which furnishes the papain of commerce. This is obtained by slashing the fruit, and collecting the milky juice in porcelain-lined receptacles, where it is allowed to evaporate. When evaporated to a granular condition, it is ready for the market and brings from $4-$6 a lb. in the crude state. The papaya has of recent years become one of the commonest table fruits of the tropics. The flesh, which is usually of a salmon-pink or yellow color, is excellent when one becomes accustomed to its peculiar flavor, and resembles somewhat a most luscious muskmelon. From its large content of papain, it may be eaten without injury in considerable quantities and assists in the digestion of other foods.
As the tree grows with great rapidity in tropical climates, it may be treated as an annual, the seeds being sown early in protected beds, well cared for and transplanted to their permanent places when well established. They will then bear fruit late in the succeeding autumn. The method of graftage described on p. 663 is preferable, however. The fruits have a considerable cavity, which, in the smaller rounded fruits, is well filled with the small brownish or blackish seeds. The firm skin, the firmness of which may be increased by selection, will permit of shipping to a distance. The plant is sometimes polygamous, and from such plants in Hawaii there have been bred types which appear to have great promise as a shipping fruit The green fruits are frequently used as vegetables, and the leaves, if cooked with tough meat, are said to make it tender, due to the digestive principle.
Hook. f. (C. cundinamarcensis, Lindl.). This is a more hardy ornamental species with numerous leaves, dark green above and pale beneath, rounded-heart-shaped, 1 1/4 ft- across, 5-lobed to the center with pinnatifid lobes: flowers green and pubescent: fruits small, pointed, 5-angled, golden yellow. B.M. 6198. -Hardy in S. Calif., but the fruits of no value as such.
Benth. & Hook. (Vasconcellea querci-folia, stem Hil.). Leaves shaped like those of the English oak, palmately 3-lobed, and containing a greater percentage of papain than C. Papaya; fruits small. - Hardy in S. Calif.
Solms. (Papaya gracilis, Regel). Habit of C. Papaya; trunk simple, 4-6 ft. high, slender, very glabrous: leaves 5-digitate, the lobes sinuate-lobed, the middle one 3-lobed, the whole blade suborbicular in outline, petioled. Brazil. Gt. 1879:986.
S. C. Stuntz.