Blue passion flower
Passifloraceae (passionfruit) family
Also known as
Where is it originally from?
Brazil to Argentina
What does it look like?
Vigorous evergreen, high-climbing vine to 6+ m with long stems that are hairless and angular when young and which have spiralling tendrils. Leaves are very thin and 5-lobed almost to the base, with each lobe 3-8 cm long and narrow. Hanging whitish purple flowers (6-9 cm diameter) with purple filaments are produced from December to April, followed by hanging round fruit (3-5 cm diameter) that ripens from green to yellow, has small amounts of inedible pulp, and contains silver-brown seeds (4 mm long).
Are there any similar species?
P. mollissima, P. mixta, and P. edulis. Alternatives: Try the native passionfruit (Passiflora tetandra) or Three King's vine (Tecomanthe speciosa), or non-native yellow jessamine (Gelsemium sempervirens) with its lovely yellow flowers. Your local garden centre will be able to recommend other non-weedy alternatives that will grow well in your area.
Why is it weedy?
This South American beauty has turned into a bit of a beast in parts of New Zealand, spreading into natural areas and smothering native plants. Its seed is spread by birds and possums, and it also grows from layering, where stems touch the ground, forming roots and new plants. Disperses effectively, grows quickly to medium to high canopy forming large masses, and stems layer. Tolerates damage, drought, hot to cold temperatures and moderate shade.
How does it spread?
Birds and possums carry seeds moderate distances. Often used as rootstock for P. edulis. Hedges, nurseries, exotic plantations, waste land, gardens and roadsides are common seed sources.
What damage does it do?
Smothers canopy, can strangle host stems, and prevents the establishment of native plant seedlings. Appears in light wells away from parent plant.
Which habitats is it likely to invade?
Disturbed and open forest, light wells and margins of intact bush, streamsides, coastline and cliffs.
What can I do to get rid of it?
1. Pull roots up (all year round). Cut off above ground or tie stems in air to prevent them coming in contact with the ground and taking root.
2. Cut down and paint stump (all year round): glyphosate (200ml/L) or metsulfuron-methyl 600g/kg (1g/L) or a product containing 100g picloram+300g triclopyr/L (100ml /L) or triclopyr 600 EC (100ml/L) or triclopyr 120g/L (500ml/L) or Banvine (200ml/L) or Woody Weedkiller (400ml/L).
3. Spray large masses on ground where roots cannot be pulled (spring-autumn): Banvine (120ml/10L) or dicamba 50g/L (24ml/L) or triclopyr 600 EC (30ml/10L) or triclopyr 120g/L (15ml/L).
What can I do to stop it coming back?
Stems layer, stumps resprout so followup and control as needed to eradicate. A few seedlings may appear in bared areas. Use herbicide only when roots cannot be pulled.