Podranea ricasoliana with its glossy foliage and abundance
of attractive pink flowers is a very showy plant, well known to
many South African gardeners. It is a vigorous, woody, rambling,
evergreen climber without tendrils.The leaves are compound and a
deep glossy green. It sends up many tall strong stems, 3 to 5 m
up to 10+ m high if left unchecked, that have long spreading branches
with a graceful arching habit. Large bunches of fragrant lilac-pink,
trumpet-shaped, foxglove-like flowers are produced all summer long
(November to March).
The flowers are carried at the branch tips of the new growth, and
are held above the foliage. The flowers terminate a branch, and
after flowering new side branches develop behind the spent flowers.
The flowers are often visited by carpenter bees (Xylocopa species).
The fruit is a long, narrow, straight, flattened capsule. The seeds
are brown, ovate and flat, in a large rectangular papery wing. It
tends not to produce many fertile seeds.
Podranea ricasoliana is a member of the Bignoniaceae, a
family of ±109 genera, mainly trees, lianes and shrubs from
mostly tropical regions particularly in South America. There are
8 southern African genera, plus 2 that have become naturalised.
The member of this family most well known to South Africans is the
jacaranda, Jacaranda mimosifolia. This tree is not indigenous
to Africa, it comes from South America, but it has become naturalised
in the warmer parts of South Africa. Indigenous species include
the Cape honeysuckle, Tecomaria
capensis and the sausage tree, Kigelia africana.
The genus Podranea contains one or two species: Podranea ricasoliana
that is found at the mouth of the Mzimvubu River at Port St Johns,
roughly half way between East London and Durban on the Eastern Cape
coast; and Podranea brycei, the Zimbabwe creeper which has
been collected from the ruins of Great Zimbabwe near Musvingo in
Zimbabwe, and from the surroundings of Nova Sofala, on the Mozambique
coast south of Beira. These two species differ only in the hairiness
of the flowers and the size of the leaves. As it is virtually impossible
to tell them apart when seen growing together many botanists regard
them as the same species. The name Podranea is an anagram
of Pandorea, a closely related Australian genus, in which
Podranea was first classified. Pandora means all-gifted.
She was the first woman of Greek mythology and was given the box
that contained all man's ills. When she opened it, they all flew
Many South African botanists suspect that this climber may not
be indigenous to southern Africa and that it was introduced here
by slave traders. All the sites where both Podranea ricasoliana
and Podranea brycei are found have ancient connections with
slave traders, who frequented the eastern coast of Africa long before
the 1600's. It has become such a widely grown garden plant in all
the warmer parts of the world that it may prove difficult to find
its real origin.
The Port St Johns creeper is well-known to gardeners in southern
Africa, Mediterranean countries, California, Florida, Australia
and Asia, and has become a popular container plant in Europe, where
it is over-wintered in heated greenhouses. It was grown in the early
1800's in British conservatories, and La Mortola Botanic Garden
near Monaco. In South Africa, White's Nursery in Durban was propagating
it in the early 1900's, and many of the South African plantings
can trace their origin to this nursery. Visitors to the World Expo
in Seville, Spain, were sheltered from the blazing Andalusian sun
by a kilometres-long pergola overgrown by Port St Johns creeper
trailing down from hydroponic troughs on top of the beams. Restaurants
and hotels on the French Riviera, the Balearic Isles and coastal
Italian cities like Sorrento grow Podranea ricasoliana in large
clay pots, training the graceful branches in patterns up their terra
Growing Podranea ricasoliana
Podranea ricasoliana is fast-growing and easy in cultivation.
It does best in full sun, in nutrient-rich, well-drained soil and
benefits greatly from regular applications of well-rotted compost
and plenty of water in summer. An established plant is tolerant
of heat, strong sunlight, wind and periods of drought. It is tolerant
of light frost and should survive a winter minimum of -7oC / 20oF
(zone 9) although it is better suited to frost free gardens. Young
plants require protection from frost, and if an established plant
is cut down by frost, it should resprout in the spring. Because
it is so vigorous and so fast it can get a bit out of control and
may grow into gutters and roof overhangs and into trees, particularly
in subtropical regions. It will need pruning to be kept neat, and
to keep it down to shrub size it should be pruned back hard every
year. Pruning will also improve flowering. The best time for pruning
is in winter or early spring just before new growth commences. It
is known to sprout where prunings have been thrown, and it is an
invasive garden escape in parts of Queensland and New South Wales
in Australia and in New Zealand.
This is an excellent plant for arbors, pergolas and carports and
is a valuable shade-giving plant in a hot climate. It is ideal for
an informal hedge or planted against a wall or a fence to create
a screen. It is a useful rambling ground cover for an embankment
as the stems root wherever they touch the soil, forming large, swollen
water- and soil-holding root clumps. It is suitable for the coastal
garden. It looks good in a large container and is a candidate for
espalier and can be pruned and trained into a weeping standard.
It has no tendrils, so it has to be tied to supports. Port St Johns
creeper mixes with Bauhinia
galpinii, Plumbago auriculata,
and Tecomaria capensis,
providing an interesting intermingling of colours. It is not a good
cut flower as the flowers drop quite soon after cutting.
This is not generally a pest-ridden plant. You may find tip/twig
wilters also called black stinkbugs or dahlia bugs (Anoplocnemis
curvipes) on young shoots, and aphids on the flower buds.
Propagation is by seed, cuttings or layering.
Although a proportion of the seed may be infertile, about 50% should
germinate. Seed should be sown in spring or during summer, in a
well-drained seedling mix, and need only be covered lightly with
the sowing mix, clean coarse sand or milled bark to stop it from
blowing away. The trays should be kept moist in a warm but shaded
position. Germination should occur in 3-4 weeks and the seedlings
potted up after the first pair of true leaves have developed.
Semi-ripe hardwood and/or hardwood cuttings can be taken in spring
or during summer. They do not require mist or bottom heat to root,
but are best in a covered frame in a well aerated medium e.g. equal
parts peat and polystyrene. Rooting period is 6 weeks, with another
6 weeks weaning period.
Podranea ricasoliana can also be propagated by means of
layering, or by removing side branches that have rooted by themselves.
To encourage Podranea to root by layering, take a low growing
stem, lay it along the ground without breaking it off the mother
plant, bend the tip to a vertical position, stake it in place and
bury or cover the part that is touching the ground with soil. The
roots should form at the sharp bend, but inflicting a wound on the
lower bent side may also help. Keep the soil moist and remove when
a sizeable root ball has developed.
Christien Malan & Alice Notten
Kirstenbosch National Botanical Garden