Babiana--TOW
Mary Sue Ittner (Sun, 13 Apr 2003 20:07:56 PDT)

The topic of the week this week is Babiana. Rachel Saunders has provided us
with an excellent introduction to this genus.

Babiana

Babiana is a large genus in the family Iridaceae, consisting of about 80
species. Most of these (about 49 species) are concentrated in the south
western Cape, with the rest mainly in Namaqualand and northern Cape. Their
range is from southern Namibia to the Eastern Cape to southern
Zimbabwe. There is one species from Socotra, off the coast of Somalia, but
it is doubtful whether it is actually a Babiana or not.

The name Babiana comes from the anglicised version of "Bobbejaan" (baboon)
- "babiaantjie" (little baboon), probably because the corms are avidly
sought by these animals. As Richard Doutt said in his book "Cape Bulbs",
it is hard to think of any other plant genus that is named after the animal
that eats it!

The plant collector Carl Thunberg used the name "Babianer" in 1882 for the
plant called Gladiolus plicatus, now named Babiana disticha, and the genus
Babiana was established by Ker in 1802.

The corms of Babiana are globose in shape, and are surrounded by numerous
reddish-brown densely matted tunics, usually extended into a neck. The
plants have very strong contractile roots which pull the corms deep into
the ground, presumably to avoid their predators (baboons, humans,
porcupines and birds).
The foliage is usually lance-shaped, pleated and mostly hairy. In some
species the leaves are abruptly cut off, leaving a ragged edge so that one
is not quite sure whether they are meant to be like that, or whether
something has eaten them!
The inflorescence is simple or branched, and the flowers are actinomorphic
(regular or symmetrical) or zygomorphic (there is only 1 plane of symmetry
in which the flower can be divided in half). The 2 lower tepals are united
below into a short of long funnel-shaped tube.
The flowers are often blue or mauve, but can be white, cream, yellow, blue,
mauve, purple, pink or red - probably the only colours missing are green
and orange! Many are beautifully scented. The seed capsules are large and
are filled with dark brown seeds.

In the new "Encyclopedia of Cape Bulbs" there is some interesting
information on pollination of Babianas. The scented species usually have
short tubes, and they are mostly pollinated by large solitary bees. Most
of the long-tubed species are not scented, and they are pollinated by long
proboscid flies. Some of the actinomorphic species with open flowers are
pollinated by bees, and the two red flowered species (B ringens and
thunbergii, formerly Antholyza ringens and plicata) are pollinated by
sunbirds (similar to humming birds, but bigger).

Most of the species are restricted in their distribution, and are often
found in very small areas only. Most grow in stony fine grained clay soils
derived from shales. As this is also prime agricultural land, many species
are now endangered. If one farmer decides to plough a field for wheat or
vines, that may be half or more of the population of a species which is
destroyed. Some species such as Babiana nana, villosa, and ringens grow in
deep sand, and B thunbergii grows in deep sand right on the beach only
meters from the sea.

All Babianas are deciduous, either winter or summer growing. Most are
winter growing, and I will concentrate on their cultivation. Like most
other winter growing (or Mediterranean climate) Irids, they start their
growth cycle in autumn when the first rains fall. The leaves push through
the soil and the plants grow. They grow through the winter, and as spring
approaches, they produce flower buds. Some species flower early in spring,
and others late, almost into summer. Most species are in seed in early
summer, and as the rains finish and the weather heats up, they go dormant
again. To successfully grow them, one needs to remember this growth
cycle. Start to water them in autumn, water through the winter, and stop
in late spring when the plants show signs of going dormant. They will do
best in a sunny aspect with free air circulation. The plants are drought
tolerant and they vary in hardiness, but probably will not like anything
below 25°F (about -5°C).
Growing medium - they all require well drained potting medium consisting of
2 parts sand, 1 part loam and perhaps 1 part compost, depending on the
species. Some growers in Cape Town use only sand, and one uses wood
shavings from pine trees. He grows almost all his bulbs and corms in this
medium, with much success.
Because of the contractile roots, Babianas pull their corms to the bottom
of the pot, and they grow best in large pots (12 inch or more).

Babianas also do well in the garden, and we have planted quite a lot out in
our beds. We have some between paving stones (in a similar situation to
their natural growth habit) and although our garden is watered year round,
they don't seem to rot and they flower profusely each spring. Our garden
soil is very sandy and well drained, and perhaps that explains it. Most of
the Babianas that are commonly grown are hybrids, mainly of B stricta, but
many of the species are far more beautiful and rewarding. The flowers are
long lasting and brightly coloured, and many are scented as a bonus.

Propagation is usually from seed, and I would recommend sowing them in
autumn. John Bryan in his book "Bulbs" suggests sowing in spring, but I am
not sure why. Perhaps this applies to people who grow bulbs in very cold
areas where the plants cannot survive the cold winters, but I am not sure
that the small plants would be big enough when they go dormant. Dormancy
occurs when the weather warms up, and it is difficult to stop them from
going dormant. We sow our seeds quite early in autumn so that the little
plants have a good 4 or 5 months of growth before they go dormant. This
means that the corm is a reasonable size and is likely to survive the long
dormancy. If you sow the seeds too late, the growth cycle is not long
enough and the corms are too small to survive dormancy. This may explain
why some plants grow well the first year from seed, but then are never seen
again. Germination is stimulated by fluctuation in temperature between
warm days and cool nights, as experienced in autumn. The day temperatures
should be about 70°F (20°C) and the nights about 50°F (about 10°C) - so
don't try to germinate your seeds in a constant temperature regime.

The last revision of Babiana is very out of date, and there are many new
species that have either been described or are waiting for description. We
find them quite difficult to identify as many are quite similar. However,
they are really rewarding species to grow as they are not too temperamental
about flowering, and generally flower most years in cultivation. In the
wild, quite a few species are fire driven, and B nana for example seldom
flowers without a fire. Each year at the IBSA (Indigenous Bulb Society of
SA) show in September many species are exhibited, so obviously they are
fairly reliable.