Exploring the Soursop
The soursop (Annona muricata) belongs to the unusual Annonaceae plant family, which also includes the sugar apple (pinha), cherimoya, and custard apple. Soursop trees are indigenous to tropical regions of the Americas and produce peculiar-looking fruit. However, what exactly is soursop and how do people grow this unusual tree?
Characteristics
The soursop tree produces fruit with a pulpy inside that is soft and highly seeded, with a spiky outer skin. These cauliflorous fruits can grow up to 30 cm (30 inches) in length, and people use the soft pulp in ice creams and sherbets when it’s mature. In fact, this little evergreen tree produces the largest fruit in the Annonaceae family.
Soursop Fruit
The fruit often has an uneven heart shape and can weigh up to 15 pounds (7 kg), with the Guinness Book of World Records noting the largest fruit at 8.14 pounds (4 kg). Though a few seeds are present, the white segments of the soursop fruit are mostly seedless.
Cultural Variations
The seeds and bark of the soursop contain poisonous alkaloids such as anonaine, muricine, and hydrocyanic acid. The name “soursop” originates from the Dutch word “zuurzak,” and its nomenclature varies greatly depending on the nation where it is grown.
Growth Requirements
The soursop tree can grow up to 30 feet (9 meters) tall and tolerates a variety of soil types, but it prefers sandy, well-drained soil with a pH of 5 to 6.5. This low-lying, bushy tree, typical of tropical climates, cannot tolerate cold and strong, persistent winds. However, it can grow up to 3,000 feet (914 m) above sea level in tropical climates.
Early Yield
Soursop trees grow quickly; they yield their first crop in three to five years from seed. Although seeds can be stored for up to six months, planting within 30 days of harvest can increase success rates since seeds will germinate in 15–30 days. Although grafting is an option for fiberless cultivars, seeds are typically used for propagation. It is best to wash seeds before planting.
Tree Care
Thick mulching is part of the maintenance for sourosop trees, as it helps the tree’s shallow root system. Pollination is hampered by extremely high temperatures (80–90 degrees Fahrenheit; 27–32 degrees Celsius) and low relative humidity, whereas it is enhanced by slightly lower temperatures with 80% relative humidity. Regular irrigation is necessary to keep souredop trees from becoming stressed and losing their leaves.
Fertilization
Apply a 10-10-10 NPK fertilizer every quarter of the year at a rate of ½ pound (0.22 kilogram) for the first year, 1 pound (0.45 kg) for the second, and 3 pounds (1.4 kg) for each subsequent year. After the first shaping is achieved, very little pruning is needed. The only pruning you should have to do is remove any sick or dead branches after harvest is over. Harvesting will be made easier if the trees are topped at six feet (2 meters).
Harvesting
Soursop fruit changes color from dark green to a lighter yellowish-green when it is ready to be harvested. The fruit enlarges and its spines soften. After harvest, soursop fruit ripens within four to five days. Trees yield two dozen fruits or more per year.
Benefits of Soursop Fruits
In addition to its delicious flavor, soursop fruit offers several health benefits: it provides calcium, iron, magnesium, potassium, phosphorus, and 71 kcal of energy. It also contains vitamins C and A. Soursop can be eaten raw or used in cakes, candies, sorbet, mousse, ice cream, and jellies. In the Philippines, the young fruit is used as a vegetable, while in the Caribbean, the pulp is extracted and mixed with sugar or consumed on its own with wine or brandy.
