Family: CARICACEAE
Other common names are tree melon and pawpaw (not to be confused with Asimina triloba). The papaya is a large herb or softwood tree, growing to a height of 10 m, although it is seldom allowed to grow as tall as this as the trunk tends to break and the fruit is more difficult to harvest. It is susceptible to the cold and cannot tolerate temperatures lower than 1°C. Mature trees are slightly more tolerant of light frosts but a sunny, sheltered position is preferable. It will grow in most soils as long as they are well drained and rich in humus. Papayas do not like acid soils, and are only moderately drought tolerant. They are fairly short lived plants, and have been used as pioneer species.
The fruits, which are produced from January to June, are large and oval in shape. They may be produced on seedling trees from as early as one year old, but will only be produced for a period of 3 - 4 years. When ripe, the skin is a yellow - orange colour and soft to the touch. Papaya flesh is soft, juicy and orange - yellow or salmon - pink in colour. It contains numerous brown - black seeds which can be used as a spice. The fruit is best eaten fresh, but can also be dried or made into jams. It is rich in calcium and Vitamins A and C. The fruits can be boiled and eaten as a vegetable when still unripe.
Nutritional composition of the papaya per 100 grams of edible portion is: Water - 88.7%, Energy - 39 calories, Carbohydrate - 10 g, Fat - 0.1 g, Protein - 0.6 g, Ash - 0.6 g, Calcium - 20 mg, Potassium - 234 mg, Sodium - 3 mg, Iron - 0.3 mg, Phosphorous - 16 mg, Vitamin A -1750 I.U., Thiamin - 0.04 mg, Riboflavin - 0.04 mg, Niacin - 0.3 mg and Ascorbic acid - 56 mgs.
The sap of the papaya is milky white, and contains an enzyme, papain. This sap is made into chewing gum, medicine (it is an aid to digestion), toothpaste arid meat tenderisers. Meat can be wrapped in a bruised papaya leaf before cooking to make it more tender. The tree is also a moderately useful bee forage plant.
Papayas are grown mainly from seed, but can also be grown from cuttings or grafted. Minimum spacing between plants is 2 m, and a pollinator is necessary. There are three types of flowers, male, female and hermaphrodite, all occurring on separate plants. Plants of the bisexual type are more suitable for tropical areas, whereas monosexual plants do better in cooler areas. One male plant to 9 females is sufficient. After the fruit has set, it is best thinned to 2 fruits per node.