Lulo / Naranjilla

Solanum quitoense

1. Identification and origin

The lulo or naranjilla (Solanum quitoense Lam.), belonging to the Solanaceae family, is a subtropical fruit crop native to the mountainous regions of Colombia, Ecuador and Peru. It is traditionally grown at altitudes between 1,000 and 2,000 m, where the cool and humid climate favours its development. The fruit is much appreciated in Andean America, especially for juices and traditional beverages.

2. Economic importance

The lulo is valued for its acidic-aromatic flavour and the high demand in the juice and tropical beverage industry. The fruit is consumed fresh, processed into frozen pulp, jams and desserts. Production is concentrated in Colombia and Ecuador, with growing interest in international markets due to its potential as an exotic fruit. The plant is also used in Solanum breeding programmes due to its resistance to some diseases.

3. Botanical characterisation

A semi-woody plant, short-lived perennial, 1.5–3 m tall. The stems and leaves are often covered with trichomes and spines, depending on the cultivar. The leaves are large, ovate, with purplish veins. The flowers are white or violet, typical of the Solanaceae. The fruits are rounded berries, with an orange skin and intense green pulp, very aromatic. The root system is shallow and sensitive to waterlogging.

4. Soil and climate requirements

It prefers cool subtropical climates, with temperatures between 16–22 °C and high relative humidity. It is sensitive to temperatures above 28 °C and to frost. It develops best in deep, fertile, well-drained soils, rich in organic matter, with pH between 5.5 and 6.5. It does not tolerate strong winds or excessive sun exposure, so cultivation under partial shade is common.

5. Main pests

• Fruit fly (Anastrepha spp., Ceratitis capitata): direct damage to the fruits.
• Mites (Tetranychus urticae): chlorosis and reduced photosynthesis.
• Aphids (Myzus persicae, Aphis gossypii): sap-sucking and virus transmission.
• Thrips (Thrips spp.): damage to young leaves and flowers.
• Nematodes (Meloidogyne spp.): root galls and decline in vigour.

6. Main diseases

• Wilt caused by Fusarium (Fusarium oxysporum): yellowing and plant death.
• Anthracnose (Colletotrichum spp.): lesions on fruits and leaves.
• Root rots (Phytophthora spp., Pythium spp.): wilt and rotting in moist soils.
• Powdery mildew (Erysiphe spp.): white coating in dry conditions.
• Solanaceous mosaic virus (TMV, PVY): mosaics, deformations and reduced production.

7. General crop management

It includes the choice of less spiny cultivars adapted to the local climate, planting in well-drained soils rich in organic matter, use of partial shading, regular irrigation without waterlogging and monitoring of pests such as fruit fly and mites. Crop rotation and solarisation reduce the pressure of nematodes and soil fungi. Harvesting should be done when the fruits reach a uniform orange colour.

Bibliographic references

• EPPO Global Database. Solanum quitoense – pests and diseases.
• CABI Invasive Species Compendium. Solanum quitoense – datasheets.
• Heiser, C. B., & Anderson, G. J. (1999). Nightshades: The Paradoxical Plants. W. H. Freeman.
• León, J. (2000). Botánica de los Cultivos Tropicales. IICA.
• Fischer, G., et al. (2014). Naranjilla. In: Yahia, E. (Ed.), Fruit and Vegetable Phytochemistry. Wiley.