On Apr 4, 2006, at 12:10 PM, Jim McKenney wrote: > Adam, before I joined this list two years ago - which is to say before > I was > much aware of the variety of temptations in the southern African flora > > But as you probably know from reading the postings on this list, most > successful growers have their plants blooming during relatively cool > weather. > > But there is a bigger problem. In my experience, these plants are > rigidly > stuck on a winter growing cycle. > > In my experience, the problem with these plants is not simply that > they are > or are not hardy; the real problem is that they are inveterate winter > growers. > > Not all of the plants you mentioned are winter growers. The big deal with southern African flora, especially those from South Africa, is knowing which are winter-growing, summer-dry plants, and which are summer-growing, winter-dry plants. These two correspond, with only a few exceptions, to which side of South Africa they are native to. If you draw a roughly north-south line roughly about 1/3 the way in from the west coast (or 2/3 the way in from the east coast), this marks the boundary of sorts between the two completely opposite annual rainfall patterns that predominate in South Africa. The west coast third of the country is the winter-rainy, summer-dry (mediterranean) rainfall pattern, and the eastern two-thirds of the country is the winter-dry, summer-rainy, more humid, rainfall pattern and climate. In whichever half of the year that rain falls, this will also be the time when plants will be in major growth. So plants and bulbs that originate from one of these two region will, as Jim says, tend to be rigidly stuck on that particular annual growing cycle. Curiously, flower season is completely independent of this--some plants bloom in the dead center of their dry season, with either no leaves or a dormant plant that will suddenly have a flower scape appear on it, like Amaryllis belladonna does with summer flowers or Aloes with winter flowers. (There are a very few plants that grow in both regions, or are native to the southern coast--which is the one anomalous, constant-rainfall-all-year region of South Africa--where you may be able to force it into one or the other growth cycle. Or it may be evergreen.) Since such a huge number of species of geophytes in particular come from the western (also known as the Western Cape) region, it might seem that almost all bulbs that came from South Africa are winter growers. But it turns out that this is not the case. So some of the ones that Jim mentioned as growing well on the U.S. east coast (like Eucomis and Crinums; also some of the Nerine species) originated in the summer-rain 2/3 portion of South Africa. This reminds of another thing to keep in mind: Some genera have evolved different species in both regions. As Rachel Saunders can tell you, you should grow them (and plant the seeds) for the different species corresponding to when the rainy season falls in their location of origin regardless of whether they are in the same genus. And Rachel, for example, will list that in her seed listings. The other factor that comes into play is that plants that come from higher elevations will tend to be hardier to colder temperatures. Thus, you find people like Jim Shields (who lives in Indiana) who are always looking for species that are native to the eastern two-thirds at high elevations, such as the Drakensberg, including Lesotho (an independent country inside of South Africa). I would think that those who live in the eastern half of the U.S. above USDA Zone 8 would be the most interested in these kinds of plants since they seem to have the highest chance of surviving in that climate. (This would be things like some of the Kniphofias and maybe some of the Dieramas. I'm not that familiar with all the natives of the higher Drakensberg areas since those are the least likely to be happy with my climate conditions here in southern California.) Anyway, for those of you so inclined to look at data plots, Mary Sue has placed on the wiki some annual rainfall plots I made several years ago of various locations throughout South Africa which I grouped into six different rainfall pattern regions. See <http://pacificbulbsociety.org/pbswiki/index.php/…> about halfway down. Okay, maybe that was too much information. But I think it's helpful in trying to guesstimate what might survive or even thrive in my particular climate. --Lee Poulsen Pasadena, California, USDA Zone 10a