Passiflora ligularis aka Sweet Granadilla

Sweet granadilla thrives in moderate temperatures between 15-29°C (60-85°F), with ideal daytime temperatures of 20-28°C (68-82°F). The plant is native to cool Andean mountain regions and prefers cooler conditions than most passion fruits. It cannot tolerate frost and requires protection when temperatures drop below 1°C, though dormant plants can briefly survive down to -1°C.

This species thrives in humid environments typical of its native Andean cloud forest habitat, where mist and fog are common. Annual rainfall of 1,000-1,200mm (tolerating 650-1,800mm) indicates preference for consistent atmospheric moisture. When grown indoors or in greenhouses, maintaining moderate to high humidity helps replicate the misty mountain conditions it naturally inhabits.

Apply a balanced N-P-K (nitrogen-phosphorus-potassium) fertilizer every 4-6 weeks during the active growing season to support vigorous vine growth and fruit production. Adjust fertilization based on soil tests and plant response, reducing or stopping fertilizer during winter dormancy. The plant benefits from humus-rich soil, so incorporating compost or organic matter also supports healthy growth.

Yes, the flowers are notably fragrant with a sweet and musky aroma. The blooms, which are 6-12 cm in diameter with greenish-white sepals and lilac-white petals, release their pleasant scent to attract pollinators including carpenter bees, honeybees, and large wasps. This fragrance is one of the ornamental features that makes sweet granadilla attractive beyond its edible fruit.

The species includes two accepted botanical varieties: Passiflora ligularis var. ligularis (the typical form) and P. ligularis var. lobata, which has more deeply lobed leaves. Additional forms historically recognized include f. lobata and var. geminiflora. However, the typical variety is what's commonly cultivated commercially for fruit production.

Sweet granadilla can be grown outdoors in USDA hardiness zones 9-11, thriving in subtropical and tropical highland climates. It grows best at elevations between 1,000-3,000 meters where temperatures remain moderate year-round. In cooler climates, it requires greenhouse cultivation or can be moved outdoors only during warm summer months. The plant needs sheltered locations protected from strong winds and frost.

Prune in early spring if necessary to control size and maintain vine structure, following RHS pruning group 11 or 12 guidelines. Regular pruning optimizes airflow, light penetration, and fruit production on this fast-growing vine that can extend 20 feet in a single season. Remove dead, damaged, or overcrowded growth, and train stems onto support structures like trellises to manage the vigorous growth habit.

Repot young plants annually in spring as they establish their vigorous root systems, moving to progressively larger containers. Mature plants can be repotted every 2-3 years or when root-bound. Use peat-free, loam-based potting compost with excellent drainage, and choose containers large enough to support the extensive vine growth (4-8 meters potential height).

Sweet granadilla propagates easily by seeds, cuttings, or layering. Semi-hardwood cuttings taken in spring or autumn root in neutral to slightly acidic compost in about 3 months. Layering is the easiest method with very high success rates.

Under glass, sweet granadilla is susceptible to glasshouse red spider mite, scale insects, and glasshouse whitefly. The plant can also be vulnerable to honey fungus and plant viruses. In cultivation, fungal pathogens including Colletotrichum species (causing anthracnose) and Fusarium solani (causing collar rot) are documented problems. Good air circulation through proper trellising and pruning helps prevent fungal issues.

Sweet granadilla flowers are pollinated primarily by large wild insects, especially carpenter bees (Xylocopa spp.), honeybees (Apis mellifera), bumblebees, and large wasps. The plant can achieve about 34% fruit set through spontaneous self-pollination, but pollinator intervention increases fruit set dramatically to 70%. Hand pollination can be used when natural pollinators are scarce. Flowers open in early morning (3:00-5:00 AM) when pollinators are most active.

Yes, the ripe fruit is highly edible and rated 5/5 by PFAF, with many considering it the best-tasting passionfruit. The soft, translucent, perfumed pulp surrounding the seeds has a very sweet and agreeable taste and can be eaten raw or made into drinks. However, only consume fully ripe fruit - unripe fruit, seeds, and rinds contain toxic cyanogenic glycosides. The fruit is rich in vitamins A, C, and K, plus phosphorus, iron, and calcium.

In traditional folk medicine, sweet granadilla has been used to regulate digestion, treat diarrhea, relieve bruises, control infections, reduce back pain, ease nasal congestion and coughing, soothe gastritis and ulcers, and help with insomnia. Modern scientific research published in Phytochemistry Reviews has validated several properties including antioxidant, antimicrobial, hypoglycemic, and neuroprotective activities. In vitro and in vivo studies confirm efficacy in reducing blood glucose levels and managing lipid metabolism.

Beyond fruit production, sweet granadilla serves multiple agroforestry purposes. The fragrant flowers provide rich nectar sources for pollinators including bees and other beneficial insects. The edible fruit supports wildlife, and the dense foliage offers shelter for invertebrates. The vigorous climbing habit makes it useful for covering structures and providing shade in tropical highland agroforestry systems.

This vigorous climber typically reaches 4-8 meters (13-26 feet) in height with a spread of 1.5-2.5 meters, producing long scrambling stems that require sturdy trellis support. The growth rate is notably fast - the vine can extend up to 20 feet in a single growing season. Plants reach maturity in 5-10 years and can begin fruiting in their second year with proper care, continuing productive fruiting for 5-7 years or more in ideal conditions.