Cyrtanthus species and hybrids Intro.TOW (part 1)
Bill Dijk (Sun, 28 Dec 2003 19:27:42 PST)

Dear All,

Cyrtanthus (sometimes called Fire Lily) is an large, entirely African genus
of approximately fifty species belonging to the Amaryllidaceae, and its
distribution is concentrated mainly in South Africa.

A number of species are easily cultivated and free flowering, and the more
"difficult" species represent a challenge to the most experienced
horticulturist, because under natural conditions flowering depends on
firing or burning of the vegetation cover. They grow in wide range of
habitats including damp bushy stream-edges, as epiphytes on other plants,
and in near desert conditions.

While a number of species are quite widespread in nature, many have
extremely restricted distribution ranges, another reason for encouraging
their cultivation.

Unfortunately they are rarely seen in cultivation, and are perhaps not
sufficiently known, ever to become popular. However, recent appearances of
collections in various countries, (including New Zealand of course) a lot
of information has come to light. A few species adapt well to general
cultivation, but for others they require a rather different treatment as to
resting periods and watering depending on their areas of origin.

Their requirements are sometimes so exact, that they will only ever be
grown by collectors and specialist growers, they will inevitably remain the
subject for the dedicated, testing their skills and patience to the limit.
Wherever possible, the natural habitat of the species should be considered,
and if possible, recreated.

The requirements of the more difficult species will have to be understood
to be successful. That's why I always grow them in (generous) containers
(various sizes according to species), not only for convenience, but mainly
to control conditions required at the different times of the season, which
often means shifting the containers, when necessary inside, or to other
parts of the nursery, when weather conditions require, like frost or to
much rain.

In general the genus prefer a very lightly shaded position, or one which
receives sun for only half the day, preferably in the morning. There are,
however a few species for instance, which actually prefer a full sun
position like C.brachyscyphus and C.obliquus, while others such as C
eucallus and C.labiatus flourish in medium shade.

With the potting medium, the main requirements should be good drainage at
all times. Our mix consist of half composted bark, a quarter pumice and a
quarter sand, sometimes more sand and pumice for the difficult species) to
which I add bonemeal or any well rotted manure or compost, plus a measure
of slow release (9-12 months) , well balanced NPK ( + trace elements), low
in nitrogen and high in potash fertiliser. An application of dilute feeding
during the growing will be beneficial and recommended as well. Don't think
with this (ours) medium the results will be magically solved.

I think the climate, the method of cultivation, potting mix, feeding, and
the know-how, all together will ultimately determine success. It's best to
treat each species separate according to their requirements..

When it comes to watering, when and how much is critical to the successful
cultivation of this species. I usually water freely when in active growth
and flowering. Knowledge of whether a particular species is evergreen or
deciduous will determine watering procedure; most deciduous species are
dormant in winter, during which time they should be kept as dry as possible.
Those species recommended for garden culture are usually tough enough to
withstand moisture during their dormant period. However, the roots of the
majority of species tend to rot very quickly if they are overwatered, or if
they receive moisture during dormancy. It is important to allow the growing
medium to dry out almost completely in between watering during the summer,
which is the main growing periods for most species.

BTW: It is a well known fact that many Cyrtanthus are lost due to
overwatering, (fungal rotting of the bulbs) especially when dormant , when
they should be dryish.

Pests and Diseases: the dreaded mealybug and red spider; (2 of the main
problems), which can create havoc and devastation very quickly. All
Cyrtanthus species are susceptible to this pest which infests the bulbs and
leaves in no time and should be sprayed and drenched ( I use
chloropyrifos based) with the appropriate insecticide where required..
Fungal rotting of the bulbs, often the cause of overwatering can also be
very destructive if not carefully managed.

My personal opinion is that Cyrtanthus like a steady, long, moderate to
warmish growing season, without sudden shocks of very cold frosty periods,
or heavy rain during dormancy, which
could also spell disaster, and should be avoided at all cost.. Growing
Cyrtanthus species was never meant to be easy, (apart from the C. elatus
and other hybrids) but if successful, will be fascinating, rewarding and
very enjoyable.

Does any PBS member on this forum grow Cyrtanthus? We would love to hear
from you and tell us your experiences with this versatile but sometimes
temperamental and fastidious species, and how you tackled some of the
little problems associated with this beautiful genus. I believe Jim Shields
has been successful with C.elatus X C.montanus and was very impressed with
its performance. Mary Sue managed to get it to flower and was delighted and
proud with her
achievement. Looking forward to hearing from you all, including the Aussies
and friends
from Europe, where the growing conditions may be different and more
challenging.

To be continued with descriptions of particular species and their requirements.

Best wishes,

Bill Dijk

Tauranga, New Zealand :annual rainfall :1250 mm.
Sunshine hours, mean annual : 2350 hours.
Temp.mean max.Summer : 25°C. winter:///15°C/.
Temp.mean min. Summer :14.5°C. Winter: 5°C.
Wet mild Winters with occasional light frost.