Soursop is an introduced tropical fruit tree that produces large compound fruits with white fibrous pulp. People eat the pulp when it ripens and softens, enjoying its sweet and sour flavour. Farmers grow it mainly in warm lowland to midland areas, especially in Ukambani (Machakos, Kitui, Makueni), coastal regions, and parts of western Kenya. It also grows under irrigation along watercourses in semi-arid and arid lowlands. Farmers use it for household nutrition and income generation, especially where it produces reliable yields.

Varieties

Farmers propagate soursop from seed, and they plant seedlings widely because seeds from good mother trees produce similar offspring. For higher yields and improved traits, farmers use grafting, budding, and cuttings. These methods help them preserve desirable characteristics such as fruit size, pulp quality, and productivity.

Climate & Soil

Soursop grows best in warm tropical lowlands and midlands below 1000 masl. The crop fails in cold conditions and cannot survive temperatures below 5°C. It requires rainfall above 1000 mm annually. The tree grows in many soil types but performs best in well-drained sandy to sandy loam soils. Farmers avoid waterlogged soils because they damage roots. Once established, mature trees tolerate dry periods, but farmers in dry zones often use irrigation to support growth.

Propagation & Planting

Farmers propagate soursop using seeds, grafting, budding, and cuttings. Seeds tolerate drying to about 5% moisture, and they remain viable under proper storage. Many farmers plant seedlings because seed-grown plants resemble the mother tree. Commercial growers prefer grafted plants for uniform performance and better yields. Farmers establish orchards at spacing of 5 m × 5 m or 4 m × 6 m. They enrich planting holes with organic matter, plant at the onset of rains, and mulch around the base to conserve moisture.

Field Management & Harvesting

Farmers weed young orchards regularly and apply mulch to reduce soil moisture loss during dry periods. They irrigate trees in dry areas to maintain growth and fruiting. Farmers apply manure or moderate fertilizer to improve performance. They prune lightly to remove weak branches and maintain a single main stem. They also improve fruit set by hand pollination where needed. The crop faces pest pressure from scale insects, mealybugs, aphids, moth larvae, termites, fruit flies, and fruit borers. It also suffers from diseases such as anthracnose, root rot, and fruit rots. Farmers harvest fruits when they reach full size and maturity, then allow them to ripen after picking because fruits bruise easily and deteriorate quickly.

Nutritional Value

Soursop pulp contains water, carbohydrates, and dietary fibre. It provides important minerals including magnesium, phosphorus, iron, potassium, calcium, copper, and zinc. It also contains B-complex vitamins such as thiamine, riboflavin, vitamin B6, and niacin, which support energy metabolism. The fruit also contains vitamin C and small amounts of vitamin A equivalents.

Uses & Market Potential

People consume soursop fresh or process it into juice. Farmers sell it in local markets and occasionally in supermarkets in urban areas of Kenya. In regions such as Kitui, Machakos, and Makueni, farmers report stable yields that support household income. The fruit bruises easily and has a short shelf life, which limits its market quality. Farmers and processors continue to explore opportunities for improved handling, marketing, and small-scale processing to increase value and reduce losses.