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 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.

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