Short Note on Passiflora lindeniana
in New Zealand
Passiflora lindeniana flowering outdoors in Helensville, New
Passiflora lindeniana fruit, about actual size
Passiflora lindeniana is a very rare tree passionflower.
Vanderplank (2010) assesses it as endangered in its native habitat of
the cloud forests of the Venezuelan and Colombian lower Andes.
Seed purchased about 1994 (under the rules of the day, prior to restrictions effected in 1998) successfully germinated and yielded five plants (2 of which I donated to a specialist in exotica). Two of the Passiflora lindeniana grown outdoors flowered after about ten years. Fruit only set and matured when flowers were hand pollinated from another tree several hundred metres away.
These small trees are very slow growing. The tallest of the three
trees is only about 3.5 meters - after 24 years of growth. Mature trees
in the wild are said to grow as high as 20 meters, and reach a girth of
1.25 meters. The trees have flowered since 2005, taking ten years from
planting out. A third plant finally flowered for the first time in
2014, at around 20 years old. The trees flower very heavily, but unless
hand pollinated, no fruit sets. The fruit are essentially inedible, so
no effort was made to set fruit until relatively recently, when I came
to appreciate how rare and valuable this germplasm is.
This is the first recorded flowering and fruiting of this species
outside in any country of the world outside its native range (pers.
comm. John Vanderplank, november 2012). (It is likely that there are
other plants of this species flowering in New Zealand, as in years past
there have been several references on the internet to specimens growing
here. At least one plant was used as a source of cuttings, so is likely
to also be ten or eleven years old, and therefore of flowering age).
All three trees growing outside are in moderate shade, one being
planted under an alder shelterbelt, the other being planted at the back
of a disused shadehouse, and overshadowed by an evergreen magnolia. The
former plant is in a moderately well drained silty sand-clay loam, the
latter is in a well drained leached sandy loam. Air temperatures here
do not fall much below about 5oC, and daytime air temperatures rarely
exceed 27oC in summer. This temperature range is probably similar to
the high elevation limits of its natural range (2,700 meters).