Solanum quitoense

Naranjilla / lulo (Solanum quitoense)
Scientific name	Solanum quitoense Lam.
Genus	Solanum
Family	Solanaceae
Order	Solanales
Growth form	Perennial shrub, often short-lived in cultivation
Native range	Costa Rica to Venezuela and Peru; Galápagos
Native biome	Humid and seasonally dry tropical uplands
Mature height	About 2 to 2.5 m
Soil	Rich, organic, well drained; mildly acidic to neutral
Flowers	White to cream, often purple-hairy outside
Fruit	Orange, aromatic berry with green, juicy pulp
Propagation	Seed; cuttings and grafting used for selected plants
Harvest	When fruit turns orange and separates readily from the plant

Naranjilla or lulo (Solanum quitoense) is an Andean fruit shrub in the genus Solanum, family Solanaceae, and order Solanales. It is grown for its aromatic orange berries, whose green pulp is commonly blended into juice. Colombia commonly calls the fruit lulo, while Ecuador uses naranjilla.^[1][2]

Description

Solanum quitoense is a spreading, herbaceous to somewhat woody shrub that can reach about 2 to 2.5 m. The large leaves are soft and velvety, commonly heart-shaped or broadly ovate, with purple coloration or veins on some forms. The stems and leaves may carry conspicuous hairs, and some plants have prickles. Flowers are creamy to white, with hairy purple coloration on the outer surfaces of the buds and calyx.^[1]

Naranjilla plant with fruits.

The fruit is a round berry, generally up to about 6 cm across. The skin changes from green to orange as it ripens, while the pulp remains green, juicy, and aromatic, containing numerous small seeds. Fruit commonly develops in clusters of several berries.^[1]

Climate and site

The species is native from Costa Rica through Panama, Colombia, Ecuador, Venezuela, and Peru, with the Galápagos also included in the accepted range. It is associated with tropical uplands and can be cultivated in warm subtropical conditions, but frost is damaging. Plants perform best with bright light and protection from strong wind; light shade can be useful in hot lowland climates.^[2]

Use a fertile, organic soil that drains freely but does not dry rapidly. A loam amended with compost and coarse material is preferable to compacted clay. Maintain even moisture during active growth, while avoiding prolonged saturation around the roots. A mildly acidic to neutral reaction is suitable; the species can tolerate a wider range when drainage and organic matter are good.^[1]

Soil

Naranjilla occurs in humid tropical uplands where soils are commonly dark, organic, and well drained, including volcanic or forest-derived loams. The native root zone stays moist but is not permanently waterlogged. Re-create that balance with compost-rich soil, coarse structure, and a mildly acidic reaction; heavy clay should be raised or amended.^[1]

Sun and humidity

Plants prefer bright light, filtered sun, or morning sun in hot lowlands rather than intense reflected heat. Native upland conditions are humid, with regular cloud or rainfall and cooler nights. Shelter from drying wind helps preserve the large leaves and supports fruit set.

Seasonal changes

Growth and fruiting follow the warm rainy season, while cooler or drier periods can slow flowering and berry enlargement. Frost is damaging. In climates with a marked dry season, maintain moisture through flowering but allow the surface to drain and partially dry between irrigations.

Propagation

Fresh seed is the usual propagation method. Clean the pulp from the seed, sow in a sterile, free-draining medium, and keep warm and evenly moist. Seedlings are genetically variable and may differ in fruit quality, spine expression, vigor, and disease tolerance. Selected plants can also be maintained by vegetative methods, including cuttings or grafting onto compatible Solanum rootstocks, but the method and rootstock should be matched to the cultivar and local disease pressure.^[1]

Flowering, fruiting and harvest

Flowering and fruiting depend strongly on elevation, temperature, rainfall, and pruning. Harvest the berries when the skin has turned orange and the fruit detaches with little force. Handle ripe fruit carefully because the thin skin and soft pulp deteriorate quickly. In climates with a pronounced cool or dry period, the main crop may be seasonal; exact harvest timing: N/A.

Fruit and uses

Lulo fruit.

The green pulp has a sharp, aromatic flavor and is most often strained or blended with water and sugar as lulo or naranjilla juice. It is also used in frozen desserts, sauces, preserves, and mixed drinks. The fruit is usually processed soon after harvest because its shelf life at room temperature is short.^[1]

Pests and diseases

Root-knot nematodes are a serious production problem in some soils. Choose clean planting material, rotate away from heavily infested Solanaceae beds, improve drainage, and remove declining plants. Disease pressure varies by region; a species-specific pest schedule: N/A.^[1]

Cultivars and selections

Commercial and local selections differ in spine expression, fruit color, plant architecture, and tolerance of nematodes or other soil problems. The thornless or less-prickly types are often preferred for handling, but cultivar names and performance are regional; a globally standardized cultivar list: N/A.

Container growing

Grow naranjilla in a large container with a rich but sharply draining mix. Provide morning sun or bright filtered light in hot climates, water when the upper layer begins to dry, and protect the plant from frost and drying wind. Replace or sterilize exhausted potting mix before replanting because soil pests can build up quickly.

Zone pushing

• Treat the plant as frost-sensitive and move containers under cover before cold weather.
• In hot lowland areas, use afternoon shade and maintain steady root-zone moisture.
• Keep the crown dry enough to avoid waterlogging while preventing severe drought stress.
• Record flowering, fruit size, nematode pressure, and winter minimums for each selection.

References

1. ↑ Growables: Naranjilla, Solanum quitoense. Plant habit, fruit, uses, soil, hardiness, propagation, and production notes.
2. ↑ Plants of the World Online: Solanum quitoense Lam.. Accepted name, range, and biome.

Image credits

• Summary: fruit.
• Description: plant with fruits.
• Fruit and uses: lulo fruit.
• Photos: flower; foliage and fruit.

Photos

Naranjilla flower.

Naranjilla foliage and fruit.