Mary Sue Ittner msittner@mcn.org
Mon, 10 Nov 2008 08:42:14 PST

I've been working on upgrading the wiki Hesperantha pages for a number of 
weeks and having finally finished them. Hesperantha is a genus in the 
Iridaceae family from southern and tropical Africa. This genus is closely 
related to Geissorhiza and sometimes the species are difficult to 
distinguish.  Most species of Geissorhiza have a style that divides above 
the anthers and in Hesperantha the style divides at the mouth of the tube. 
Hesperantha species grow in summer rainfall areas and winter rainfall areas 
in a variety of habitats, at low elevations and high. Flowers are generally 
not open very long during the day. Some of them open in the morning and 
close early to late afternoon. Others open early to late afternoon and 
close late afternoon to evening. Some open at dusk and stay open all night. 
Those are usually fragrant and pollinated by moths. The same species may 
have flowers that open during the day however and are not fragrant and they 
are generally pollinated by bees. Other species with long tubes are 
pollinated by long probiscid flies.  All of the species but one grow from 
corms. One is rhizomatous and used to have its own genus, Schizostylis. 
This species, Hesperantha coccinea, grows in very wet areas and the red 
form of it is pollinated by butterflies.

There is very little difference in the flower structure of many of the 
species and looking at the pictures many of them are very difficult to tell 
apart. There are size differences and corm differences and differences in 
when they bloom (fall, winter, spring, summer) and habitat differences 
however. One that is different and very beautiful is Hesperantha vaginata. 
It is yellow, usually with dark tips. It opens early afternoon on warm days 
in late winter, early spring and closes a few hours later. It is pollinated 
by beetles. We understood that it is endangered and only grows in the 
Nieuwoudtville reserve, but in 2006 when we visited in South Africa we 
found it growing in mass on a farm. You could pay to drive through the farm 
and there were a lot of flowers in bloom so it was well worth the money and 
the time. So if you look at the Hesperantha pages, I hope you won't give up 
before you see those habitat pictures. Cameron McMaster has photographed 
many of the summer rainfall species and in fact discovered one of them, 
Hesperantha stenosiphon, a long tubed pink species with dark anthers. 
Photos were added from him, my husband and me, Alan Horstmann, and Rod 
Saunders. Mary Wise from Australia also gave me permission to add a photo 
of hers of Hesperanth luticola. This one grows in the Roggeveld and after 
seeing a picture of it in one of Rod's slide shows, I really wanted to grow 
it, but have not had any luck. Mary reported that she lost hers as well.

As I was writing this note I decided to link to an article Cameron wrote in 
the IBSA bulletin about a succession of blooms of this genus in the Eastern 
Cape. When I was searching for the link I found the Hesperantha revision 
which I would have loved to have had when I started the major project. I 
tried to find it online when I first started, but couldn't.  Sigh. Thanks 
to Mobot for making two informative articles on this genus (also one on 
pollination) available to the public online. I added the links for all 
three of these to the Hesperantha page:

I hope those of you who do not know this genus will enjoy learning about it 
and everyone will enjoy looking at the pictures. Many of them are habitat 
pictures. The fragrant Hesperantha cucullata form (I grow one form that 
opens earlier and is not fragrant) that blooms during the night can fill 
your house with fragrance if you bring it inside and during the night the 
flower goes through all kinds of movements to make itself available to the 
pollinators. Hesperatha latifolia is one I'm especially fond of since it is 
a bit longer blooming and has bright pink flowers in winter. It is native 
to Namaqualand, but still grows well in my wet Northern California garden.

Mary Sue

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