Guyabano (Annona muricata)

About Guyabano

Guyabano (soursop or graviola) is one of the largest and most distinctive tropical fruits found in the Philippines. Annona muricata, a member of the Annonaceae (custard apple) family and cousin to atis (sugar apple), produces spiny, heart-shaped green fruit that can weigh 1 to 5 kilograms — dramatically larger than most Philippine fruits. The tree grows 5 to 8 meters tall with dense, glossy-leaved foliage and an architectural, low-branching habit.

The fruit's exterior is covered in soft, fleshy spines that flatten as it ripens. Inside, the white, fibrous flesh has a creamy texture and a unique tangy-sweet flavor often described as a blend of strawberry, pineapple, coconut, and citrus. Numerous flat, dark-brown seeds are distributed throughout the pulp. The combination of sweetness and tartness — the "sour" in soursop — makes guyabano particularly refreshing when processed into juice, ice cream, and shakes.

In the Philippines, guyabano is valued primarily as a processed fruit rather than fresh eating, because the seedy flesh is easier to enjoy when strained into juice or churned into ice cream. Guyabano has also gained attention in recent years due to unverified claims about health benefits — it is important to separate traditional culinary use from unproven medical claims, as discussed in the FAQ section below.

History & Discovery

Guyabano originated in the tropical lowlands of Central and South America, with its center of diversity in the Caribbean and Amazonian regions. Like its cousin atis, it was brought to the Philippines by Spanish colonial traders during the Manila-Acapulco galleon era (16th to 17th century). The Tagalog name "guyabano" is derived from the Spanish "guanábana," itself borrowed from the indigenous Taino language of the Caribbean.

Annona muricata was formally described by Linnaeus in 1753. The species name "muricata" means "rough" or "prickly" in Latin, referring to the fruit's characteristic soft spines. The tree naturalized successfully in the Philippine climate, growing wild along forest edges and cultivated in backyards across Luzon, Visayas, and Mindanao.

In recent decades, guyabano has been the subject of extensive laboratory research on acetogenins — bioactive compounds found in the leaves, seeds, and bark of Annonaceae species. While some laboratory studies have shown cytotoxic effects on cancer cell lines, these findings have not been replicated in human clinical trials, and no reputable medical authority endorses guyabano as a cancer treatment.

How to Plant Guyabano in the Philippines

Guyabano is most commonly grown from seed, though marcotting and grafting produce faster-fruiting trees.

1. Obtain seeds or marcotted seedlings. Extract large seeds from ripe fruit, wash, and dry for 2 to 3 days. Seeds remain viable for several months stored cool and dry. For faster fruiting, purchase marcotted or grafted seedlings.
2. Sow seeds. Plant 2 to 3 centimeters deep in seedling trays. Keep moist and warm. Germination takes 15 to 30 days — faster than atis seeds.
3. Prepare the planting site. Choose a sheltered, full-sun location protected from strong winds — guyabano branches are brittle and snap easily in typhoons. Dig a hole 60 centimeters wide and deep. Mix soil with 5 to 10 kilograms of compost.
4. Transplant. When seedlings are 30 to 50 centimeters tall, transplant to the prepared hole. Space 5 to 6 meters apart — guyabano develops a wide, spreading canopy. Water deeply and mulch.
5. Stake and protect from wind. Stake young trees for the first 1 to 2 years. Position near a wall or windbreak if possible.
6. First harvest. Seed-grown trees fruit in 3 to 5 years. Marcotted trees in 2 to 3 years. Harvest when the skin turns from glossy dark green to dull yellowish-green and spines flatten. Handle carefully.

Care Guide

Sunlight

Guyabano grows best in full sun to partial shade — 6 to 8 hours of sunlight daily. Young trees actually benefit from some afternoon shade protection during their first year. Mature trees tolerate more shade than atis and can produce fruit even in partially shaded locations, though yield is lower.

Watering

Water deeply every 2 to 3 days during the dry season for young trees. Established guyabano (3+ years) has moderate drought tolerance but produces larger, juicier fruit with consistent moisture. Unlike atis, guyabano does not benefit from drought stress — steady moisture year-round is preferred. Ensure drainage to prevent root rot during heavy rains.

Soil

Guyabano thrives in deep, well-draining, fertile soil with a pH of 5.5 to 6.5 — slightly more acidic than most Philippine fruit trees prefer. Rich organic matter is important for good fruit production. The tree does not tolerate waterlogging — plant on raised mounds in flood-prone areas. Amend heavy clay with compost, sand, and rice hull ash.

Humidity & Temperature

Guyabano thrives at 25°C to 35°C with high humidity (70 to 90 percent) — matching Philippine lowland conditions. The tree is more cold-sensitive than atis, with growth slowing below 20°C. Strong winds are the greatest environmental threat — the brittle branches and large fruit make wind damage a serious concern during typhoon season. Position in sheltered locations.

Fertilizer

Apply balanced fertilizer (14-14-14) at 300 to 500 grams per tree every 3 months. Supplement with potassium-rich fertilizer during fruit development for better fruit quality. Top-dress with 5 to 10 kilograms of compost annually. Guyabano is a heavier feeder than atis and responds well to organic amendments.

Pruning

Annual pruning is important for guyabano. Remove dead, damaged, and crossing branches. Thin the canopy to improve air circulation and reduce disease pressure. Keep the tree to 4 to 5 meters through selective pruning for easier harvesting. Remove low-hanging branches that drag on the ground. Pruning also reduces wind resistance, decreasing typhoon damage risk.

Growing Medium Options

Edible Uses & Nutrition

Guyabano is primarily consumed as a processed product — the seedy, fibrous flesh is best strained into beverages and frozen desserts rather than eaten whole.

Culinary Uses

• Guyabano juice. The most popular preparation — flesh blended with water, strained, sweetened, and served over ice. Widely sold in restaurants, carinderia, and street-side stalls.
• Guyabano ice cream. Strained pulp churned into artisanal ice cream — one of the most prized Filipino ice cream flavors, with a distinctive tangy-creamy character.
• Guyabano shake. Pulp blended with milk, condensed milk, and ice for a rich, creamy smoothie.
• Guyabano candy and pastillas. Cooked pulp sweetened and shaped into candies — a regional specialty in some Visayan and Mindanao provinces.
• Guyabano tea. Dried leaves steeped in boiling water — a popular wellness tea, though health claims should be viewed critically (see FAQ).

Nutritional Profile

Guyabano is a good source of vitamin C, dietary fiber, and potassium. It provides moderate amounts of B vitamins and minerals. The fruit is relatively low in calories for its satisfying, creamy texture, making it a nutritious choice for beverages and desserts.

Air Quality & Oxygen

Guyabano is a medium to large tree with dense, glossy foliage that provides excellent shade coverage — 15 to 30 square meters under a mature canopy. The tree makes an effective shade tree for patios, parking areas, and outdoor living spaces in Metro Manila yards. Its evergreen habit in Philippine conditions ensures year-round shade and oxygen production.

The dense canopy filters dust and airborne particulates, while the large leaf surface area contributes substantially to oxygen generation. Guyabano's low-branching, spreading form creates a natural umbrella that cools surrounding areas through transpiration — reducing ambient temperatures by several degrees under the canopy during the hottest hours.

Toxicity & Safety

Important note on health claims: Despite viral social media posts, guyabano is NOT a proven cancer cure. Laboratory studies on annonacin show cytotoxicity against some cancer cells in vitro, but no human clinical trials have confirmed these effects. The DOH and WHO do not endorse guyabano as cancer treatment. Never substitute guyabano for conventional medical care.

Common Pests & Diseases in the Philippines

• Mealybugs. White cottony clusters on fruit, leaf joints, and trunk crevices. The most common guyabano pest. Spray with neem oil or insecticidal soap. Control ants that farm mealybugs.
• Fruit borers (Cerconota anonella). Larvae bore into developing fruit causing internal decay. Bag young fruit with paper or cloth bags. Remove and destroy infested fruit.
• Anthracnose (Colletotrichum gloeosporioides). Black, sunken lesions on fruit during wet weather — a major post-harvest problem. Prune for air circulation, apply copper fungicide preventively, and harvest fruit at the color-break stage.
• Root rot (Phytophthora spp.). Fatal in waterlogged conditions. Ensure excellent drainage. Plant on raised mounds in flood-prone areas. No effective cure once established.
• Scale insects. Small, brown bumps on branches. Apply horticultural oil spray. Heavy infestations cause branch dieback and reduced vigor.

Frequently Asked Questions

Sources & References

• Plants of the World Online — Annona muricata L. Royal Botanic Gardens, Kew. powo.science.kew.org
• Stuart, G.U. (2024). Philippine Medicinal Plants — Guyabano. stuartxchange.org
• USDA FoodData Central — Soursop, raw. fdc.nal.usda.gov
• Champy, P. et al. (2005). Annonacin, a lipophilic inhibitor of mitochondrial complex I, induces nigral and striatal neurodegeneration in rats. Journal of Neurochemistry, 88(1), 63–69.
• World Health Organization — No endorsement of Annona muricata as cancer treatment.