[pbs] Haemanthus--TOW (continued)
Mary Sue Ittner
msittner at mcn.org
Mon Dec 6 10:19:12 EST 2004
Here is the rest of the Haemanthus introduction:
Dr Snijman has classified Haemanthus into four groups of closely allied
species:
H. humilis Group
1. H. humilis Jacq.
2. H. carneus Ker Gawler
3. H. montanus Baker
4. H. avasmontanus Dinter
H. crispus group
5. H. crispus Snijman
6. H. barkerae Snijman
7. H. tristis Snijman
8. H. namaquensis R.A. Dyer
H. albiflos group
9. H. albiflos Jacq.
10. H. deformis Hook f.
11. H. pauculifolius Snijman
H. coccineus group
12. H. sanguineus Jacq.
13. H. canaliculatus Levyns
14. H. pumilio Jacq.
15. H. lanceifolius Jacq.
16. H. amarylloides Jacq.
17. H. graniticus Snijman
18. H. nortieri Isaac
19. H. coccineus L.
20. H. dasyphyllus Snijman
21. H. unifoliatus Snijman
22. H. pubescens L.f.
The Haemanthus humilis group, which are summer rainfall species, flower
from mid summer. Haemanthus avasmontanus is known from the type specimens
only, collected from the Auasberge, south east of Windhoek in central
Namibia. The winter rainfall species, which include both the H crispus and
H. coccineus groups flower in autumn. A number of species in the winter
rainfall region are locally endemic and under considerable threat. The most
notable of these are H. tristis, H canaliculatus, H. pumilio and H.
lanceifolius. The H. albiflos group are evergreen and flower in winter or
early spring.
My personal experience of Haemanthus is confined largely to the summer
rainfall species, and more specifically to those which occur in the Eastern
Cape. My observations of Haemanthus in the Eastern Cape were published in
the September 2004 edition of Veld and Flora, the organ of the South
African Botanical Society.
I have been fascinated by the variability of local populations,
particularly of the H. humilis humilis group which occur over a wide range
of habitats. H. humilis is widespread but occurs in isolated and localised
populations in specialised habitats, which is probably the reason for the
variation between populations. The most spectacular form is one we call
"Giant" which we observed with binoculars growing on a steep cliff in full
shade on the opposite bank of the Great Kei River. I had to swim the river
and scale the cliff to get seed, and now have a well established population
in the nursery as a seed source and bulbs of various ages for sale. It has
leaves as large as 60cm in diameter and it has an enormous flower head. In
sharp contrast is a miniature form growing near King Williams Town with
tiny flower heads on stems less than 20cm in height, which we call "Dwarf".
Two other noteworthy variations of H. humilis in the Eastern Cape are an
early flowering form from the Graaff Reinet area of the central Karoo. This
form has small cerise flowers with bright yellow stamens very, very
attractive. We have also collected seed from a pure white form with
pubescent leaves growing in Acacia thicket in the Stutterheim district of
which we now have stock.
Closely allied to H. humilis is the enigmatic H. carneus known from only a
very few disjunct populations. This rare species flowers in January and is
distinguished by a looser, widely spreading umbel and stamens included well
within the perianth, the only known Haemanthus with this feature. It has
the same growth pattern as H. humilis, with leaves emerging just after the
flowers and persisting to late spring. It occurs in Acacia thicket and
grassland on a mountain near Somerset East. One wonders whether H. carneus
should be considered separate from H. humilis on the basis of the small
difference mentioned above. What confuses the issue is a further form which
occurs some 40km further west on Bruintjieshoogte, which has stamens the
same length as the perianth tube, a feature shared by the white form of H.
humilis from Stutterheim mentioned above. These seem to be intermediate
between H. carneus and H. humilis. Isolated populations of Haemanthus with
included stamens occurring near Escourt in Natal and near Jagersfontain in
the Free State, have been attributed to H. carneus. Charles Craib writing
in IBSA Bulletin No. 48 (1999) expressing the same reservation, also
queried this distinction, basing his query on the fact that populations of
H. carneus and H. humilis hirsutus occur near to each other in identical
habitats near Estcourt. Dr Snijman, commenting in the same publication
suggests that the shorter stamens of H. carneus could be an adaptation to
exploit a different pollinator to H. humilis, and that should this be the
case, it is possible that two taxanomic entities might be reproductively
isolated in the wild despite their shared physical habitats and close
geographic proximity to one another.
Haemanthus montanus occurs in isolated local populations from the Eastern
Cape northwards. The Bedford district is probably its most southern
extremity. H. montanus grows in small areas of poorly drained shallow soil
with an impervious substratum. It completes its annual cycle in four to
five months, the period during which its fairly hostile habitat remains
moist. It occurs in dense stands, the large cream flowers appearing from
December to January, rapidly followed by two upright leaves. The seed
ripens by mid-February and germinates rapidly around the parent plants. The
leaves dry off and blow away by the end of May when all signs of the bulb
population have vanished.
The most widespread Haemanthus in the Eastern Cape is H. albiflos which is
amazingly adaptive and versatile in its habitat. It is a particularly
desirable and easy to grow garden subject and is also suitable as a ground
cover in areas of semi-shade. It is equally at home in deep shade on forest
floors, on rocky sea shores exposed to salt spray, in coastal dune forest,
on cliff faces in hot river valleys where it clings in large clumps to
crevasses in full sun, and in shady places on high altitude inland mountain
ranges. It is evergreen and multiplies vegetatively, as well as from seed.
The attractive white flowers appear in May and the ripe seeds are carried
in equally attractive clusters of scarlet fruit.
It is very surprising to find the West Cape species, H. coccineus, which
flowers in autumn, occurring as far east as the Keiskamma River valley near
Hamburg It grows here in Valley Thicket vegetation together with a small
form of H. albiflos which flowers in winter, so they don't hybridize. H.
coccineus occurs from here, a summer rainfall region, westwards through the
winter rainfall region of the Western Cape and up to the arid regions of
Namaqualand and Namibia, an enormous range of 2000+ kilometers and climate
variation! The flower stems can be reddish, or blotched with red. and the
leaves have varying degrees of stripes and dots on the underside.
Recently we moved to Napier in the Western Cape where H. coccineus and H.
sanguineus grow in the wild. Both species have very similar flowers and
occur in the same habitats. They are only easily distinguishable by the
leaves, and since they bloom before leaves emerge, it is sometimes a puzzle
to be sure of the species. In contrast to H coccineus, H. sanguineus has
tough, leathery leaves, rounder in shape with a distinct reddish margin and
always flat on the ground. There are no markings on the underside of the
leaves.
Haemanthus are easy to propagate from seed. Seed will germinate soon after
ripening but germination can be retarded by keeping it in a fridge. Sowing
of seed is easiest after a strong radicle has formed, when they can be
placed in rows in a seed box of well drained seedling mix with the radicle
in the soil and the seed on the surface. Water sparingly but do not allow
the seed box to dry out. Leaves form rapidly. Most species retain their
leaves for the first year. Seedling bulbs can be kept in seed boxes for a
year or two after which they should be transferred to individual
containers. The secret is well drained soil rich in organic matter. Winter
rainfall species should be kept dry in summer and only watered again when
growing season commences in late summer. Summer rainfall species are more
tolerant of watering all year round and should not be allowed to dry out
completely in their dormant phase. Evergreen species should be kept moist
all year round. Species from high altitudes such as H. humilis, H. carneus
and H. montanus should be fairly hardy and are able to tolerate 5 to 6
degrees of frost.
We have found H. albiflos, H. coccineus and H. humilis "Giant" the easiest
to propagate and fastest growers. While not difficult to cultivate, other
species are rather slower to develop. It will be interesting to have
comments from other growers concerning their experience in propagating
Haemanthus. The wonderful flowers that are eventually produced are ample
reward for patience and care in growing them.
Cameron McMaster
africanbulbs at haznet.co.za
Please consult the Haemanthus wiki page to see photos of the species
described in the introduction:
http://www.ibiblio.org/pbs/pbswiki/index.php/Haemanthus
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