[pbs] Cyrtanthus species and hybrids Intro.TOW (part 1)

Bill Dijk daffodil at wave.co.nz
Sun Dec 28 19:27:42 EST 2003


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.









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