Passion fruit have evergreen vines and beautiful flowers

Press, Volume CXI, Issue 32660, 16 July 1971, Page 11

Passion fruit have evergreen vines and beautiful flowers

The species of passion fruit plant present us with some beautiful flowering and attractive evergreen foliaged vines, which can also provide prolific crops of delicious fruit.

Only about four of the 350 species comprising the genus are of major commerical importance, and even fewer are at all widely grown or even well known in this part of the world. Of these only Passiflora edulis—the black and purple passion fruit and its hybrids, can be said to be readily obtainable and is usually the one found in the home garden. Other countries also grow the banana passion fruit and one or more of the three granadillas (giant, sweet and yellow).

Although regarded as only half hardy, passion vines have been seen to grow 'in and survive severe conditions. However, to get the best out of them—they can be most prolific croppers with a main crop usually ripening in late summer and, under favourable conditions, a small flush in early spring—optimum conditions are necessary.

The important points in their successful culture is a site with a northerly aspect, ample sun. shelter from damaging winds, a fertile, moisture-retentive but freedraining soil, good support and adequate training. Drainage is important to

avoid root rot, a disease which can severely affect the plant to the extent of complete collapse of the vine. It is more likely to occur in heavier soils.

Passion fruit is particularly sensitive to weather, particularly around flowering time. To ensure fruit set, pollination must occur on the first morning after flowering as pollen production lags behind the development of receptivity in the female part (stigma) of the flower. Even then, fertility can be adversely affected by high temperatures, sudden cold changes, and even by damping of pollen by rain or in watering of the plant(s). Plants can be raised from the seed from which considerable variation can result unless it is obtained from a reliable source. Grafted plants are favoured by .many as it is claimed that these ate more resistent to fungus and virus diseases, a claim which has not been substantiated. (Some root stocks also have a tendency to sucker.) Yet another way of raising pas* sion vines is from semi-ripe cuttings. <■ As passion fruit are gross feeders planting should be done is well-enriched soils. Thorough pre-planting cultivation is recommended, and the addition of a complete fertiliser incorporated in the top soil —also well in advance of siting the vine. A mixture comprising 2 parts sulphate of ammonia, 1 part superphosphate and 1 part potash (by weight) should be applied at the rate of Alb a plant. Thereafter this mixture can form the annual application increased to a miximum of 51b for a mature plant. Because of its cropping habit, half the annual fertiliser application should be given at the beginning of September and the rest about December, rather than all at once. Support needed

The vine will need support, and all too often this aspect is neglected for so long that the plant becomes such a tangle that it cannot be unravelled. For this reason, the need to provide an adequate trellis or framework on which the plant can be trained right from the start cannot be overemphasised. Not only does such support provide a means for the plant to climb and grow freely but it enables sunlight to reach all the leaves, flowers and fruit, allows for satisfactory air circulation and assists in ripening and picking of fruit. Several of the strongest shoots should be separately trained up and along a framework of spaced wires or laths. During the first year only the leaders—six are adequate for most purposes—should be allowed to grow unchecked and all other growth pinched out. Once the main framework has been developed laterals and secondary laterals arise which carry the fruit, the first of which can be expected about fifteen months after planting. Once a vine has become well established' annual pruning is necessary. This is usually done in early spring, to keep the plant “open” and to encourage fruit which is borne on current season’s growth. All dead, diseased, weak and excessive shoots should be removed first. Then fruited laterals should be shortened back to the secbnd bud from the leader. As leaders age they should be constantly renewed by selecting suitable vigorous new vines to take their place. It is imperative not to

prune too early as a severe frost could well damage the plant to the extent of complete crop loss for the season. Moisture Needs Cropping and fruit flavour and even plant growth can be impaired through lack of moisture through spring and summer. The roots actually prefer a moist, cool root run over the wanner months of the year and to achieve this a mulch around the base is well worth while. During dry and hot spells the soil should be frequently checked to ensure that sufficient moisture is present. This does not imply that plants must be maintained in swamp-like conditions which is so often taken as the meaning of “moist conditions.”

The black or purple passion fruit and various hybrids such as Crackerjack are the most widely grown. However, the yellow banana passion fruit is as hardy if not more so, and although containing more seeds and being a more rampant grower I regarded it as superior in taste and in the amount of pulp content. It can be readily distinguished from the purple varieties not only by the shape and colour

of fruit but also by the ■similar differences in flower, as can be seen in the accompanying illustrations. The banana passion flower is tubular and red in colour, the purple one clematis-like and mauvish-coloured.

Spanish and Italian travellers discovered the passion vine in the tropical regions of Brazil early in the nineteenth century. They thought it represented the implements of the Crucifixion and from this it is that the plant has derived both its potential and popular names. Inside the petals of the flower of this particular vine is the corona, a series of coloured rays or filaments. These were taken to represent the crown of thorns or, by others, thought to be emblematic of the halo. The five stamens suggested five wounds while others considered that they looked representative of hammers which were used to drive in the nails. The three styles with capitate stigmas were thought to look like the latter. The digitate-like leaves suggested the hands of the persecutors, and the long auxiliary coiling tendrils by which the plant supports itself, were considered to represent the cords or the scourges.