How to grow Passionfruit

Flowers on new vines each year, needs a strong climbing support. It is reasonably hardy and if exposed to the cold will die back to the ground each year. Mulch the crown deeply to protect the plant from the cold. Prefers moderate temperatures throughout the year and is sensitive to severe frost². In hot areas, they should be planted on cool slopes, and in cooler areas, they should be planted on warmer slopes². Average monthly temperatures should not exceed the range of 5-29°C (41-85°F)², although they are hardy down to 1°C (34°F). Granadillas prefer a high relative humidity and well-distributed rainfall of not less than 1 200 mm/year (irrigation can supplement low rainfall)².

Granadillas have deep root systems, and so thorough, deep (at least 80 cm/32 inches) soil preparation is necessary, as they may otherwise develop shallow root systems in compacted soil². Well-drained soil is important as they are sensitive to excessively wet conditions². Avoid clay soils². Proper soil development ensures good root development, better soil drainage (less runoff), better utilisation of nutrients, better disease tolerance, and increased fruit size and yield².

Add calcium, lime and phosphate before planting, if necessary². Like all vigorous growers, they are heavy feeders. Add compost, a balanced slow-release fertiliser (such as 10-5-20 all-purpose fertilizer) and mulch as required.

Granadillas are quite water-hungry, and may need up to 15 litres per plant per day in summer (8 litres per plant per day in winter)².

Lifespan is about 3 years².

A sturdy trellising system is necessary, as it will need to support a heavy weight. If using wooden trellising, be sure the wood is termite resistant². The vines should be trained systematically so that the framework gets a good shape². Tie a selected leader of each plant loosely to a stake or train it up a
string until it reaches the top wire. Remove all side shoots, but not the leaves. • As soon as the main leader reaches the top wire, it is progressively
wound loosely round the wire as it grows².

Pruning

Pruning or thinning out is necessary when the granadilla vine becomes unproductive. It is done mainly to:

• Stimulate new growth
• Promote healthy vine growth because light and air can now reach the inner parts, which discourages pests and diseases
• Remove all dead, old, injured and diseased parts of the vine
• Prevent vine overlap
• Facilitate spraying.

Selective pruning
The main leader is trained along the wire and the fruiting laterals are trained so that they hang down freely. Cut off all laterals at ground level if they start growing along the
ground².

Severe pruning
Severe pruning is not necessary if granadillas are grown on a short-term basis (12-18 months), because it can lower production². The main leader is trained along the wire and the laterals are trained to hang down. As soon as the laterals reach the ground, they are cut back just above ground level. After about 12 to 15 months all the laterals are cut back about 300 mm (or 46 nodes) from the main leader. The plants are usually pruned during July/August in the Southern hemisphere (ie, late winter)². To produce an out-of-season crop, the vines may be pruned during September/October (early spring)².

Seed is best sown fresh, but can be encouraged to germinate by pre soaking for 48 to 72 hours in a shallow container in a warm place. It is often soaked in some fruit juice such as orange juice. Viable seed usually sinks during this time. After soaking, and planting the seed only shallowly in the compost, use bottom heat, 70-80°F (21-27°C), and do not exclude light. Germination is variable and can take a few weeks to a few months, during which time the compost must not dry out.

To enhance germination, the seed together with the pulp can be placed in a plastic container and allowed to ferment for 1 to 3 days. It is then thoroughly washed, dried and sown as soon as possible.²• Seed may be stored in closed containers at 13°C (55°F) for about 4 months².

Seed can be sown in trays or polyethylene bags (75-150 mm/3-6 inches in diameter and 200 mm/8 inches in height). If possible, sow 2 seeds per hole of the seedling tray or per bag and select the stronger of the two². Push a thin stake into the soil next to the emerged seedling so that it can be trained up the stake. Remove the developing side shoots regularly. • The seedlings should be ready for transplanting when they reach a height of 300 to 400 mm (11-15 inches). • Select only seedlings for transplanting which have dark green leaves and are free of any symptoms of nematode or fungal disease infestations².

Used sterilised soil².

Soil temperature should be kept higher than 20°C / 68°F to ensure good germination.

Prefers a sunny position, with plenty of room to grow and support to climb.

The seedlings should be ready for transplanting about 3 to 6 months after sowing the seed². The optimum time for transplanting (in the Southern Hemisphere) is during August/September (ie, early spring). The yellow granadilla is more susceptible to cold than the purple granadilla and yellow granadilla grafted onto purple granadilla rootstock should therefore not be planted in areas where frost occurs².

Ensure that temperatures are mild (minimum night temperatures should be around 5°C / 41°F) and all chance of frost has passed before planting out, as Passionfruit is a half hardy plant.

Depending on the time of transplanting, the first fruit is usually ready for harvesting 6-9 months after planting². At about 18 months after planting the crop should have reached its full bearing potential². Thereafter, there are 2 main crops annually, namely a summer crop and a smaller winter crop. Some climates sometimes have a third crop during Autumn. A limited quantity of fruit will, however, be available throughout the year².

Fruit for immediate consumption should be picked when the fruit has a deep purple colour² – this fruit shrivels quickly (and is hence unsuitable for marketing), but is still tasty. Fruit for the fresh market, or for storing for a little while, should be picked when the fruit is fully developed with with a light purple colour².• Fruit should be harvested early in the morning².

Fruit usually ripens from flowers after about 80 days⁴.

Seeds do not keep well and are best sown than stored. Granadillas are general grown from seedlings. If seed is used, be sure to use seed from ripe fruit selected from healthy plants². Scoop out the contents of a granadilla that has been cut through.• Wash the contents to separate the seed and pulp.• Dry the seed in the shade and sow it in seedling trays or planting bags filled with a well-prepared soil mixture.²• Seed may be stored in closed containers at 13 °C for about 4 months².

These estimates for how long Passionfruit takes to sprout, grow and harvest are from real observations from real gardeners, right around the world.

The latin ‘edulis’ means “edible”.¹

It is the national flower of Paraguay³.

Passion fruit, Pasionaryia, Purple Granadilla, Purple Passion Fruit, Passion Vine

Passiflora edulis Sims

¹ The meaning of Latin plant names

² Cultivating Granadillas – National Department of Agriculture ARC-Institute for Tropical and Subtropical Crops

³ Wikipedia entry on Passiflora edulis

⁴ How to grow passionflower