Passiflora caerulea 'Blue Crown'

Passiflora caerulea is also known as the Blue Crown Passion Flower or Hardy Passionflower. It is an extremely fast growing and beautiful plant. P. caerulea sparks with 10cm (4in) flowers with white petals and blue filaments. It is popular with gardeners because of its intricate, scented flowers that have an almost surreal appearance.

It is one of the hardiest Passion Flowers, dying back in colder climates but hardy to -12°C (10°F) It will regrow from deep roots after even severe freezes. They are evergreen in tropical climates, but deciduous where winters are cool and may be grown outdoors in most fertile, moist but well-drained soils or indoors as a container plant. Provide support for climbing stems and shelter from cold, drying winds.
A delightful perennial climber that succeeds in full sun in most soils.

• Awarded the RHS Award of Garden Merit
  Passiflora caerulea has been awarded the Royal Horticultural Society’s Award of Garden Merit (AGM).

Sowing: Sow in late winter/late spring and late summer/autumn.
Prior to Sowing, Soak the seeds for 24 hours. Soaking is beneficial in two ways; it can soften a hard seed coat and also leach out any chemical inhibitors in the seed which may prevent germination. 24 hours in water which starts off hand hot is usually sufficient. If soaking for longer the water should be changed daily. Seeds of some species swell up when they are soaked. As each seed swells it should be removed and sown before it has time to dry out. and the remainder pricked gently with a pin and returned to soak. Sow seeds in a peaty compost, 'just cover' with ¼ in of soil as the seeds need light to germinate.

Germination of Passiflora can occur in weeks or take several months. If your home is on the low side of 20°C (68°F), your seeds will benefit from bottom heat with an electric soil warming cable kit, or a heating mat. It will stimulate early growth, and help seeds to germinate and cut the germination time by half. Cover the top of the pot with clear plastic so the humidity will remain high.
When you see some tiny plants starting to sprout, open the top of the pot, a little each day, so that the new seedlings don't go into shock from the humidity being lowered too quickly. Prick out each seedling as it becomes large enough to handle, transplant into 7.5cm (3in) pots. Pot on as required. These plants have very fragile white roots and should be handled with care when potting up.
Grow on under glass in loam-based potting compost in full light with shade from hot sun. You may need to water your plants on a daily basis during the hottest summer months. During the winter the roots should be kept moist, but as growth will be much slower you will probably only need to water once a week, depending on growing temperature. Fertilize at least once every two weeks in the growing season.
If planting outdoors, gradually acclimatise to outdoor conditions for 10 to 15 days before planting out, space 30cm (12in) apart. Passion flowers like full sun and will scramble over trees and shrubs to get it.

Pot grown plants:
If the pot is too large or they have an unrestricted root run then the whole plant will simply get bigger but it will refuse to flower and produce fruits.
By limiting the pot size you are limiting the ability to grow and this is seen as a threat, so the natural mechanism is to produce seeds for the next generation. A suitably sized pot for an adult plant would generally be of 30cm (12in) in diameter.

Cultivation:
Pruning is a must to keep the vine healthy. Prune off less vigorous growth and occasionally prune back vigorous growth to promote flowering. When established, and without care, the passion fruit can easily overtake other garden plants, shading them from sun. Prune in late winter or spring, by shortening side shoots to within three to four buds of the permanent framework of branches. This induces more compact growth and promotes the formation of flower buds in the shortened shoots.

Plant Uses:
Fences or trellis work or scrambling up trees and shrubs. Patio/Container Plants, Sub-tropical or Wall-side Borders. Container, Indoor / Greenhouse Plant

Origin:
Passiflora caerulea, commonly known as the Passion Flower or Blue Passion Flower, is native to central and western South America. It is the national flower of Paraguay.

Nomenclature:
The genus name Passiflora is derived from the Latin passio meaning ‘passion’ and flos meaning ‘flower, in reference to parts of this plant seemingly representing aspects of Christ.
The species name caerulea is from the Latin meaning ‘blue’, in reference to the filaments of the flowers.
The Passion flower symbolises spirituality. 16th Century missionaries in South America named it the passion flower because they believed it symbolised the death of Christ - the sepals and petals represented the disciples; the double row stood for the crown of thorns, and the stamens stood for the wounds.

The National Collection:
The National Collection of Passiflora is kept at - Lampley Road, Kingston Seymour, Clevedon, North Somerset, BS21 6XS, United Kingdom. Tel : (0044) 01934 833350.
Visitors are welcome but please call before visiting to confirm the opening times.