|Annona subsp. var.|
Describe the plant here...
|Standard Cyclopedia of Horticulture|
Annona (Latin, year's harvest, suggested by the Haitian name anon applied to one of the species. Commonly spelled Anona, but Linnaeus used the double n). Annonaceae (Richard, 1808). Custard-apple. Araticu. Tropical and subtropical woody plants cultivated for their fleshy fruits and for ornament. Leaves 2-ranked, alternate, devoid of stipules: fls. perfect, solitary or in clusters, extra-axillary, often opposite the Lvs. and sometimes subterminal; calyx usually gamosepalous, 3-parted; petals typically 6. in 2 series, but the inner series in some species reduced to small scales or even wanting; stamens numerous, crowded on the receptacle, the fleshy filament bearing a pair of linear parallel pollen-sacs on its back, these opening extrorsely by a longitudinal slit and capped by the expanded hood-like connective; pistils many; the ovaries usually clothed on the outside with minute hairs and containing a single erect ovule at the base: fr. a syncarpium, formed by the growing together of the carpels and receptacle into a fleshy mass; seeds containing a large wrinkled endosperm with small basal embryo.—Trees and shrubs, over 50 in number, chiefly from Trop. Amer., but a few from Afr., and several now widely cult. in the warmer regions of both hemispheres. Several species have been successfully introduced into southern California and Florida. Some of those cited in catalogues and horticultural publications are merely forms of old species and others are generically distinct. Amongst these names are A. mexicana, which was a catalogue name used by Loddiges; A. excelsa of Humboldt & Bonpland, a species never fully described, the flowers and fruit of which are entirely unknown; and A. africana, an obscure species based by Linnaeus upon an American specimen with lanceolate, pubescent leaves. A. trilobata and A. obovala are Asimina triloba and Asimina obovata, A. asiática of Linnseue is not an annona at all but a rubiaceous plant. Morinda citrifolia; while A. asiática of Loureiro is A. reticulata, and A. asiática of Vahl is A. squamosa. A. Forskahlii of De Candolle (A. glabra, Forsk., not Linn.) was based upon a specimen of A. squamosa growing in cultivation in Egypt; to A. squamosa must also be referred A. triflora of Mociño & Sessé, while A. longifolia of these authors is undoubtedly A. reticulata, and their A.fruticosa is A.globiflora of Schlechtendahl. A.aurantiaca and A. macrocarpa are Brazilian species, the names of which were erroneously applied to certain cultivated forms in southern California; while A. suavissima is only a horticultural variety of A. Cherimola, and A. cinérea of the Antilles a form of A. squamosa. A. palustris of Linnaeus is identical with his previously described A. glabra, and the latter name must take precedence in accordance with accepted rules of priority. A number of species described as annonas belong to other genera. Among them are A. amplexicaulis and A. grandiflora of the islands of Mauritius and Madagascar, which belong to the genus Pseudannona. A. Mannii of Oliver, an African species which has a branching inflorescence very different from that of the genus Annona. has been assigned to a new genus Anonidium by Engler & Diels; and A. Perottetia of A. De Candolle has been placed in the genus Unonopsis by R. E. Fries. Annona obtusiflora of Tussac, together with A. mucosa of Jacquin, must be placed in the genus Rollinia under the name R. mucosa, and to this genus should also be assigned the Brazilian biriba, which is probably Rollinia orthopetala, a species with large, fleshy fruit of delicious flavor, successfully introduced into Florida from Para. The climbing Annona uncinata of Lamarck belongs to the genus Artabotrys. A. pyriformis, also a climbing shrub, of Mauritius, the fruit of which is unknown, belongs undoubtedly to some other genus. For Annona longifolia see Duguetia. See also Rollinia, Artabotrys and Cananga.
While the annonas succeed beet on a heavy loam, most species can be grown on light soils and under adverse conditions. The custard-apple (A. reticulata) thrives on the Florida keys in a semi-naturalized state; the cherimoya (A. Cherimola,) grows and bears abundantly on steep calcareous cliffs in Central America; the sugar-apple (A. squamosa) is successful on dry and sandy soils with practically no attention whatever. The situation best adapted to them is a sloping piece of ground, for, with the exception of A. glabra, they are intolerant of stagnant water about the roots.
The cherimoya, probably the hardiest of the genus, withstands temperatures as low as 26° F. without injury, and reaches perfection only in a comparatively cool climate. The soursop (A. muricata) is one of the tenderest species; the sugar-apple and the custard- apple are somewhat hardier; all three are successfully grown in southern Florida, but not in California.
Propagation is usually effected by means of seeds; the most highly valued species, however, such as the cherimoya, are budded or grafted.
Seeds will retain their vitality for several years, and if planted in warm weather or under glass will germinate in a few weeks. If in a greenhouse, they may be planted at any season of the year; otherwise, it is best to. plant only during spring or early summer. Sow thickly in flats or pans of light, porous soil containing an abundance of humus, covering to the depth of ½ or ¾ inch. When the plants are 3 or 4 inches high, they should be potted into 3-inch pots; care should be taken to see that the soil is perfectly drained, and waterings should not be too frequent or copious. When the plants have attained a height of 8 or 10 inches, they may either be shifted into larger pots or set out in the open ground; in the latter case, they must have careful attention until they have become established and made considerable growth.
Both budding and grafting have proved to be readily applicable to the annonas, either in the open ground or in pots, under glass. Several different species have been used for stocks, A. Cherimola proving the most satisfactory thus far in California, as it is best adapted to that climate; A. glabra has been found to be the most vigorous and satisfactory in Florida.
Shield budding, essentially the same as practised with the citrous fruits, is the method most commonly used. The work is best done in spring, shortly after the sap has begun to flow, the time varying, of course, according to locality and season. Stocks should be from ⅜ to ½ inch in diameter; seedlings of this size will be eighteen months to two years old. Budwood from which the leaves have dropped, and of about a year's growth, is the most desirable. It is important that the buds be cut large,—about 1½ inches in length. —as they are likely to have difficulty in starting and be choked out, on account of the thick bark and rapid callousing of the annonas, if they are too small. The incision may be made either in the form of a T or an inverted T, raising the bark with care so that the delicate tissues lying under it will not be injured, and inserting the bud with as little pressure as possible. Waxed tape should be used for tying. Three or four weeks after insertion, the buds should be unwrapped, and, if they have united with the stock, re-wrapped loosely, lopping the stock at a point 5 or 6 inches above the bud. The wrap should not be removed until the bud has made a growth of several inches.
For grafting, two-year-old seedlings are used, the operation being a simple cleft-graft, using a scion of well-matured wood from which the leaves have dropped.
Cuttings of well-ripened wood can be rooted under glass, with bottom heat. This method of propagation is not widely practised, however.
The annonas, when grown from seed, vary greatly in regard to productiveness as well as size, color, form, texture and quality of fruit. In southern California, many large seedling cherimoyas have been grubbed out because they were unproductive, while others produce fruit of such poor quality as to be of no value. Careful attention to culture will assist in improving the quality and size of the fruit, but the only sure way to perpetuate choice forms and eliminate all possibility of the tree turning out to be inferior is to propagate by some asexual means.
Most species come into bearing when three or four years old. Few named varieties have been established, and these are probably confined to the cherimoya.
In some countries, the annonas arc subject to certain fungous diseases and insect pests, notably the mealy-bug. As a class, however, they seem to suffer less from these pests than most other fruit trees. They require very little pruning.
Fruits must be picked when mature,—to avoid their falling to the ground and becoming bruised,—and laid away for a few days before they are ready for eating. If they are to be shipped any distance, they must be packed in some material, such as excelsior or straw, that will allow good ventilation, each fruit being wrapped in a piece of strong paper. The selection of the toughest-skinned varieties adds greatly to the facility with which they can be shipped.
Pests and diseases
- Standard Cyclopedia of Horticulture, by L. H. Bailey, MacMillan Co., 1963