Passion fruit is a perennial vigorous vine, which grows to give oval or round shaped fruit. This vine is native to tropical regions of southern Brazil; this succulent fruit is also grown in Uganda and mainly in central and western regions. The fruit is easy to grow as it gives back to the farmer in only 8-12 months.
NAADS distributes passion fruits seedlings to meet the commercialization objective of Government of Uganda. Support to production of passion fruits targets especially Women and Youth groups; and other socio-economically vulnerable groups.
- The purple passion fruit is subtropical and prefers a frost-free climate.
- The plant doesn’t grow well in intense heat.
- The yellow passion fruit is tropical and is even much more intolerable to frost.
- Both these passion fruits need protection from the wind. Generally, the annual rainfall should be at least 35 inches.
- Passion fruit vines make good container specimens but require regular maintenance.
- They perform well indoors.
- The passion fruit is a vigorous, climbing vine that clings by tendrils to almost any support.
- It can grow 15 to 20 ft. per year once established and must have strong support.
- It is generally short-lived (5 to 7 years).
- The evergreen leaves of passion fruit are alternate, deeply 3-lobed when mature and finely toothed.
- They are 3 to 8 inches long, deep green and glossy above, paler and dull beneath and, like the young stems and tendrils, tinged with red or purple, especially in the yellow form.
- A single, fragrant flower, 2 to 3 inches wide, is born at each node on the new growth.
- The bloom, clasped by 3 large, green, lifelike bracts, consists of 5 greenish-white sepals, 5 white petals and a fringelike corona of straight, white-tipped rays, rich purple at the base.
- It also has 5 stamens with large anthers, the ovary and triple-branched style forming a prominent central structure.
- Purple passion fruit is self-fruitful, but pollination is best under humid conditions.
- The flowers of the yellow form are perfect but self-sterile.
- Carpenter bees are the most efficient pollinator, much more so than honey bees.
- Wind is ineffective because of the heaviness and stickiness of the pollen.
- The flowers can also be hand pollinated.
- The nearly round or ovoid fruit, 1-1/2 to 3 inches wide, has a tough rind that is smooth and waxy and ranging in hue from dark purple with faint, fine white specks, to light yellow or pumpkin-color.
- Within is a cavity more or less filled with an aromatic mass of double walled, membranous sacs containing orange-colored, pulpy juice and as many as 250 small, hard, dark brown or black, pitted seeds.
- The unique flavor is appealing, musky, guava-like and sweet/tart to tart.
- The yellow form has generally larger fruit than the purple, but the pulp of the purple is less acid, richer in aroma and flavor, and has a higher proportion of juice (35-38%).
- Numerous hybrids have been made between purple and the yellow passion fruit, often yielding colors and other characteristic intermediate between the two forms.
- The vine, especially the yellow form, is fast-growing and will begin to bear in 1 to 3 years. Ripening occurs 70 to 80 days after pollination.
- Plant passion fruit vines in full sun except in very hot areas where partial shade is preferable.
- The vine can be rather rampant, so it is important to plant it next to a chain link fence or install a strong trellis before planting.
- The plants can also be trained into an attractive arbor.
- Passion fruit vines grow on many soil types but light to heavy sandy loams with a pH of 6.5 to 7.5 are the most suitable.
- Excellent drainage is absolutely necessary.
- Also, the soil should be rich in organic matter and low in salts.
- If the soil is too acid, lime must be applied. Because the vines are shallow-rooted, they will benefit from a thick layer of organic mulch.
- Regular watering will keep a vine flowering and fruiting almost continuously.
- Water requirement is high when fruits are approaching maturity.
- If the soil is dry, fruits may shrivel and fall prematurely.
- Passion fruit vines are vigorous growers and require regular fertilizing.
- A good choice is 10-5-20 NPK (or other nitrogenous fertilizer such as DAP) applied at the rate of 1.5 KG per plant 4 times a year.
- Too much nitrogen results in vigorous foliage growth at the expense of flowering.
- Passion fruit vines should always be watched for deficiencies, particularly in potassium and calcium, and of less importance, magnesium.
- Plants that have been damaged by frost should receive a generous fertilizing after the weather has warmed.
- Pruning is necessary to keep the vines within bounds, to make harvest easier and to keep the plants productive by maintaining vigorous growth.
- In warm winter climates prune immediately after harvest. In areas with cool winters prune in early spring.
- As a general rule remove all weak growth and cut back vigorous growth by at least one third.
- In very hot climates allow a thick canopy of foliage to grow around the fruit to prevent sunburn.
- Because of their mass, passion fruit vines are difficult to cover when freezes threaten, but the layers of leaves help protect the inner branches from frost damage.
- The plant will also usually come back even when frozen to the ground.
- The best strategy is to grow the vines against a wall or deck or in a patio.
- Any kind of overhead protection provides additional benefits.
Seasons and Harvesting
- The different flowering seasons of the purple and yellow passion fruits have been mentioned under “Pollination”. In some areas, as in India, the vines bear throughout the year but peak periods are, first, August to December, and, second, March to May.
- At the latter time, the fruits are somewhat smaller, with less juice. In Hawaii, passion fruits mature from June through January, with heaviest crops in July and August and October and November.
- With variations according to cultivar, and with commercial cultivation both above and below the Equator, there need never be a shortage of raw material for processing.
- Ripe fruits fall to the ground and will roll in between mounded rows. They do not attract flies or ants but should be collected daily to avoid spoilage from soil organisms. In South Africa, they are subject to sunburn damage on the ground and, for that reason, are picked from the vines 2 or 3 times a week in the summertime before they are fully ripe, that is, when they are light-purple.
- At this stage, they will reach the fresh fruit market before they wrinkle. In winter, only one picking per week is necessary.
- For juice processing, the fruit is allowed to attain a deep-purple color. In India and Israel the fruits are always picked from the vine rather than being allowed to fall. It has been found that fallen fruits are lower in soluble solids, sugar content, acidity and ascorbic acid content.
- The fruits should be collected in lugs or boxes, not in bags which will cause “sweating”. If not sent immediately to processing plants, the fruits should be spread out on wire racks where there will be good air circulation.
- For the Ugandan scenario, the yields are 650 plants/acre with each vine producing about 20KGs which translates to about 13,000 KG of passion fruit. Since prices range between Ugx 1,002 and Ugx. 2,004, revenue per acre can range between Ugx. 8,857,485 and Ugx. 26,572,455.
- Underripe yellow passionfruits can be ripened and stored at 68º F (20º C) with relative humidity of 85 to 90%.
- Ripening is too rapid at 86º F (30º C). Ripe fruits keep for one week at 36º to 45º F (2.22º-7.22º C).
- Fruits stored in unperforated, sealed, polyethylene bags at 74º F (23.1º C), have remained in good condition for 2 weeks. Coating with paraffin and storing at 41º to 44.6º F (5º to 7º C) and relative humidity of 85 to 90%, has prevented wrinkling and preserved quality for 30 days.
Pests and Diseases
- Passion Vine Mite
- This occurs during dry weather in the warm season.
- The infestation defoliates the younger portions of the vines but not the terminus but not the terminus.
- Makes brown blemishes on the fruits.
- Passion Vine Bug
- Feeds on flowers and young green fruits.
- Vegetable Bug
- Attacks the growing tips and sucks out the sap when it is at an adult stage.
- Leaf Beetles and weevils
- Chew the foliage.
- Injure and cause stunting of young seedlings in nurseries.
- In dry weather, they feed on leaves and fruits, leaving them defaced and prone to shriveling and eventually falling off prematurely.
- Cause extreme thickening of the roots (root-knot nematode).
- Note that the yellow passion fruit is rather resistant to nematodes.
- Other types of nematodes include the spiral nematode and the lesion nematode.
- Brown spot
- Commonly occurs in dry weather.
- One of the leading diseases in yellow passion fruits.
- Leaf spots are visible.
- Lesions on the branches are also visible.
- Crinkling of leaves is also evident.
- Septoria spot
- Has more numerous and smaller spots the brown spot.
- It is prevalent during summer and fall seasons.
- It is spread by dew, rain and overhead irrigation.
- It is believed to have a hand in the contraction of base rot which is spread through injury from mowers or other mechanical equipment.
- Fusarium wilt
- This arises from a soil-borne fungus.
- There is visible splitting of the trunk and shedding of the bark on the plant.
- The first signs are chlorosis, necrosis and defoliation.
- It can be remedied by grafting the purple-yellow hybrids onto the yellow passion fruit rootstock because it is more resistant.
- Woodiness or Bullet
- This is caused by a virus.
- The disease appears as small misshapen fruits with a thick rind and small pulp cavity and is a serious plague of the purple passion fruit.
- The yellow passion fruit is rather resistant to this disease.