Monday 26 March 2018

Haemanthus Blog


Haemanthus
Early Autumn in Victoria is the time that most growers of this genus of 22 species of bulbs from southern Africa, including South Africa, Lesotho, Swaziland and Namibia, associate with.  The majority of the species are summer dormant and seem to respond to seasonal changes such as late summer storms, cooler nights and perhaps shorter daylight hours by sending up their unique candle like spikes of flowers encased in a usually wax like cluster of red spathal bracts, resembling a paint brush, hence one of the common names of Paint Brush Lily.  Flowers are soon followed by usually fleshy large leaves which remain until dormancy again commences in late spring.  This description typifies the form and habit of perhaps the most commonly grown species and certainly the one with the widest distribution in the wild, Haemanthus coccineus.  There are numerous forms of Haemanthus coccineus grown, most of them differentiated and identified by the collection locality eg Napier form, Knersvlakte form, Colchester form, etc.  There are also some interesting colour variations of the forms we grow in our gardens.
Although quite a number of the species within this genus follow this pattern of growth and are superficially similar to Haemanthus coccineus in flower, very few of these will be seen in cultivation as their demands are very particular and plant material for propagation ie seeds, are rarely, if ever, available.  Species with visually close floral affinities to Haemanthus coccineus include Haemanthus barkerae, H canaliculatus, H crispus, H dasyphyllus, H graniticus, H namaquensis, H nortieri, H pubescens (including a number of sub-species), H sanguineus and H unifoliatus.
There is another group that follows this summer dormant, winter growth pattern but although flowering is triggered similarly, the bracts surrounding the flowers are far less obvious being more papery and often less colourful, as are the flowers.  Species in this group include Haemanthus amarylloides (and its sub-species), H avasmontanus, H lanceifolius, H montanus, H pumilio and H tristis.  It should be noted that H montanus has a short early dormancy and tends to send up its flowering spikes in late spring and early summer.
A third group and possible the most rewarding along with Haemanthus coccineus, consists of two species, Haemanthus carneus and H humilis (2 sub-species).  Both of these are quite easy to grow and differ mainly in their spherical head of light pink and occasionally white  flowers (rather than the paintbrush).  They also flower earlier, somewhere between H montanus and H coccineus ie mid summer, come into leaf earlier and have an earlier but short dormancy during spring.  There are quite a number of forms of H humilis including the Giant form with leaves up to 250mm wide and perhaps 750mm long and dwarf forms from the King William Town and Georgetown areas respectively in South Africa.  These have leaves only 25mm wide and maybe 40mm long.  Other forms grown are generally identified by their locality eg Thomas River form, Quanti form, etc.  Although I grow a number of forms in the open garden, they are generally better managed in containers using a very well drained growing medium.
The forth and final group are the evergreen species of Haemanthus albiflos, H deformis and H pauculifolius, all of which have white flowers in a paintbrush like cluster.   H albiflos hybridises with H coccineus and a number of excellent colour forms of this are occasionally available.
Unfortunately, as a genus, bulbs are slow to offset, with some species not offsetting at all.  As a result, only the good offsettters such as H coccineus and H albiflos are readily available.  That said, all species grow readily from seed if you can obtain it but are generally slow to mature, taking 5 and often more years to reach maturity.  It is understandable why then, seed grown plants can fetch a high price.   Seeds of Haemanthus sp are recalcitrant ie they germinate automatically, without the stimulus of soil or water.  They cannot be stored for any length of time although storing in the fridge will delay germination a few weeks. Haemanthus humilis is one species that normally sets seeds in good quantity, especially if there are a number of different forms grown for good cross pollination.  Collecting and growing from seed is the subject of a further blog.
 Bruce

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