Annona muricata
| Soursop (Annona muricata) | |
|---|---|
| |
| Scientific name | Annona muricata[1] |
| Genus | Annona |
| Common names | Soursop, graviola, guanabana |
| Family | Annonaceae |
| Order | Magnoliales |
| Native range | Tropical America[2] |
| Mature size | About 7.5–9 m in a university arboretum record[2] |
| Sun | Full sun to partial shade[3] |
| Soil | Moist, well-drained; pH 5–6.5 in regional guidance[3] |
| Years to fruit | 2–4 years reported for seedling trees in Guam[3] |
Soursop (Annona muricata) is a tropical fruit tree cultivated for its soft, aromatic fruit. It is frost-sensitive and is best suited to warm, humid sites where the root zone can remain moist without becoming waterlogged.[2][3]
Description[edit | edit source]
The tree is described as low-growing and about 7.5–9 m tall in a University of Arizona arboretum record. Flowers can arise from the trunk and branches. The dark-green fruit has a spiny surface and turns yellow-green as it ripens.[2]
Fruit traits vary substantially among seed-propagated trees. An in-situ study of 28 trees in the Soconusco region of Chiapas reported group-mean fruit weights of approximately 376–1,580 g, seed counts of about 31–131, and total soluble solids of 6.82–11.83 °Brix. These groups describe measured variation in the sampled population, not formal cultivars or universal fruit specifications.[4]
Cultivation[edit | edit source]
Soil and water[edit | edit source]
Use a fertile, moist but well-drained soil; the Guam production guide gives a pH range of 5–6.5 and cautions against saturated conditions. The Arizona arboretum guidance gives a similar mildly acidic, well-drained range of pH 5.5–6.5.[2][3] Drainage is especially important where irrigation is frequent or heavy rain follows a dry period. In a pronounced dry season, maintain even root-zone moisture rather than alternating severe drying with saturation; the exact irrigation interval depends on soil and climate.
Sun and humidity[edit | edit source]
Full sun supports production, although partial shade is included in the Arizona guidance. Soursop is a frost-sensitive tropical tree and is better suited to humid conditions than to exposed cold or dry sites.[2][3] Provide airflow around the canopy while protecting young trees from strong, drying winds; the Guam guide discusses windbreaks and pruning as part of orchard management.[3]
Seasonal changes[edit | edit source]
Flowering and fruit development are not governed by one universal calendar. In a field study of ungrafted, seed-propagated trees in two rainfed orchards in Nayarit, Mexico, flowering stages extended over 132 and 153 days, fruit development over 119 and 109 days, and fruit-maturity stages over 8–10 days at the two sites. Those measurements are specific to the orchards, their climate and management, rather than a fixed schedule for every tree.[5]
Keep moisture available during warm, actively growing periods and reduce irrigation only as needed to match rainfall and drainage; do not allow the root zone to remain saturated. Protect the tree from frost whenever cool-season temperatures threaten, because the species is described as frost-sensitive.[2]
Propagation[edit | edit source]
Seed propagation is widely documented and is the method used for the trees in the Mexican field studies. The Guam guide reports seed emergence in approximately 15–30 days under its conditions and also discusses softwood cuttings, air-layering and grafting.[3] These timing and success figures should be treated as regional production guidance rather than a guarantee for every seed lot.
Cutting, budding and grafting are also recorded in the Arizona and Guam horticultural accounts.[2][3] A review of soursop biotechnology notes that micropropagation responses vary with explant, genotype and culture medium, so a protocol developed for one selection should not be assumed to transfer unchanged to another.[6] A Tropical Fruit Forum grower reported three preliminary green-on-green grafts onto in-ground Honeyhart cherimoya in southern California; the report had not established whether the grafts survived winter, and it provides no evidence that cherimoya rootstock confers hardiness.[7]
Flowering, fruiting, and harvest[edit | edit source]
Flowers may form on the trunk and older branches. The Nayarit phenology study found deficient natural pollination and proposed hand pollination as a way to improve the uniformity of fruit size and shape under the studied orchard conditions.[5] A separate grower account described a container-grown plant that flowered singly and was hand-pollinated with one-day-old pollen; the post did not provide complete climate details, so it is a practical observation rather than a general pollination rule.[8]
The Guam guide reports seedling bearing in 2–4 years in Guam.[3] In another attributed Tropical Fruit Forum account, a grower reported a seedling fruiting after four years, with about 20 flowers producing six fruits in that season. The reported fruit weighed just over 1.2 kg and was described as yellowish, soft, crisp-creamy and sweet-sour; the account does not provide a verifiable date or complete location, so it should not be used as a general bearing-age or quality benchmark.[9]
Harvest fruit as it approaches physiological maturity and is beginning to change from dark green toward yellow-green; the postharvest study used fruit harvested at physiological maturity, while the Arizona record describes yellow-green color at ripeness.[2][10]
Fruit and uses[edit | edit source]
Soursop fruit has soft flesh and a spiny exterior. The Chiapas characterization shows why fruit from seedling trees should be evaluated individually: weight, seed number, soluble solids and other measured traits differed among the sampled groups.[4] The fruit is climacteric and perishable. In a controlled postharvest experiment using two selections from an ungrafted Nayarit orchard, storage at 15 °C extended shelf life to up to eight days without observed chilling injury under the tested conditions. That result applies to the tested selections, temperature and handling regime, not to every fruit or storage system.[10]
Concentrated extracts and medicinal supplements should not be treated as equivalent to ordinary culinary fruit. An in-vitro study of extracts from Annonaceae supplements and fruit pulp, including A. muricata, found neurotoxicity signals in cultured human neuronal cells at the tested concentrations. The experiment does not establish a safe dietary dose, clinical risk from normal servings, or therapeutic benefit; it does support avoiding unsupported medicinal claims and treating concentrated products cautiously.[11]
Pests and diseases[edit | edit source]
The Guam production guide identifies anthracnose, fruit rots, root rots, mealybugs and aphids as production problems in its regional context.[3] Good drainage, canopy airflow and sanitation are relevant where wet conditions favor rot, but the guide's pest and disease list should not be read as a universal ranking for every climate.
Container and marginal-climate growing[edit | edit source]
Soursop is frost-sensitive, so a container can make seasonal protection easier, but the supplied grower reports do not establish a reliable container size, winter temperature limit or long-term yield expectation. One Tropical Fruit Forum grower described a plant started from seed in 2005, first flowering at age five, and grown in a living-room setting; the account lacks verifiable publication date and complete climate details. Another grower attempted grafting onto cherimoya in southern California without a reported winter result.[8][7] These reports are useful examples of experimentation, not evidence of universal indoor performance or cold hardiness.
Photos[edit | edit source]
References[edit | edit source]
Image credits[edit | edit source]
- Annona muricata 1.jpg: “Soursop fruit (Annona muricata) photographed at Jardin d'Éden, Réunion Island.” Photograph by Damien Boilley, CC BY 2.0.
- Annona muricata-guanábana.jpg: “Soursop (Annona muricata) fruit.” Photograph by Tim Gage, CC BY-SA 2.0.
