Agapanthus in intercontinental U.S.?

Well, I would think you could grow them as "annuals", or winter the bulb over indoors, as is done here in zone 3... but I assume you are more likely wondering if there are species/varieties that are hardy in your area and tolerant of your conditions?  

yes. I think there are some named cvs. that will survive outdoors here. I'm interested in those of course, but more so in species.

Santa Fe's climate is similar to Denver's, nominally zone 5b, although I think it's closer to 6 now, with most moisture from winter snow or summer monsoon. First freeze is generally around October 7 and last freeze around May 7, depending on exact elevation.

I have been growing Agapanthus in Colorado for over 40 years (I first bought them in the 1960's from a magnificent nursery in British Columbia: Alpenglow gardens, and have had them ever since).

We get good seed set and have grown more from our seed: I have to say that seedlings often do not overwinter (although self sown seedlings do great). And fall planted agapanthus are not as reliable as those you put in the spring.

Once they are established, I think -25 is no problem. Agapanthus campanulatus ssp. patens is a very high elevation plant in the Drakensberg which grows on the very cold summit where snow in midsummer is common. I shall never forget the display on Sentinel my first visit when cliffs were draped with blue Agapanthus jostling with fawn pink Dierama dracomontanum and a hundred other choice alpines in between (Moraea, Eucomis, Orchids galore, Helichrysum, Osteospermum, you name it! It may have been the most spectacular display of color I have ever seen anywhere.

This pictures shows just a few of the clumps gracing the South African plaza meadow in late July.

This is actually the news I was hoping to learn about here... hardy Agapanthus!  Panayoti, love those blue agapanthus, this goes to the top of my list.

At a local NARGS seedling sale this autumn, I picked up a couple tiny Agapanthus campanulatus ssp. patens plants (for ~25 cents each), and just for kicks I threw them into the ground on the warm south side of the house near the foundation.  I think they're are goners, but taking cues from Panayoti, I see that I must try again with spring plantings to get them more established before the onset of winter.  If I ever do get these growing here, I'll try and make the plant more at home by underplanting with Osteospermum jucundum, one of the best hardy Osteos around.

Here are two photos of O. jucundum, taken back in 2001 and 2002.  For 10 years growing outside, I'd say this South African plant is hardy in Zone 5.  In the view showing both light and dark pink flowers, the dark pink one is O. barbarae, which is much coarser a plant and died out here.  For the last 5 years O. jucundum lived outside in the rock garden (rather than in plunged pots) and made a good size mat... it grows and spreads slowly from a branched woody caudex.  Last year, mice tunnelled up and through the mat while under snow all winter and nearly destroyed it, leaving behind 3 small growing pieces.  It came back during the summer, so I hope it is enough to perpetuate the plant for many more seasons to come.

That is exactly what I hoped to read, Panayoti. Now I need to find A. campanulatus ssp. patens for planting this spring. All that construction last year has provided me lots of new garden space and I'm excited to get them going!

Actually, Barbara, I think just plain old 'Headbourne Hybrids' are mostly A. campanulatus: we've had good luck just growing these as well as the wild collected stuff. And they're a tad more widely available..

And Osteospermum names are a problem: I have always thought the Osteo that grows on Sentinel (near Mount-aux-sources in the north of the Natal Drakensberg looked different from the O. jucundum I've seen elsewhere in the Drakensberg. If you have old copies of AGS bulletin, I recall Helen Milford actually doing a species description of Osteospermum barberiae var. compactum from that Sentinel area.. On my first enchanted visit there in January of 1994 it was in full spectacular bloom: I recall that they almost all had the fabulous violet-pink color that characterizes the 'Purple Mountain' cultivar sold by Plant Select http://www.plantselect.org/plant_details.php?comment=noww&plant_number=21 The picture doesn't really do this color justice: it's velvety and rich purple-violet-rose, a really scrumptious shade. I have no doubt this cultivar derives from the Sentinel area--they looked just like that...

But the thlot plickens! I got a pinch of seed there years ago and grew it, and the progeny were all various soft pinks, just like Mark's plant (and like the jucundum from elsewhere in the Draks). Since then I've grown a white flowered plant nearby that's related to these, and they've hybridized in my garden (see below), where they are very happy campers and bloom all summer and just generally delight me. I am anxious to get true jucundum from elsewhere in the Drakensberg to really compare and see what's up with this very good group of plants.

Kelaidis wrote:

And Osteospermum names are a problem: I have always thought the Osteo that grows on Sentinel (near Mount-aux-sources in the north of the Natal Drakensberg looked different from the O. jucundum I've seen elsewhere in the Drakensberg. If you have old copies of AGS bulletin, I recall Helen Milford actually doing a species description of Osteospermum barberiae var. compactum from that Sentinel area.. On my first enchanted visit there in January of 1994 it was in full spectacular bloom: I recall that they almost all had the fabulous violet-pink color that characterizes the 'Purple Mountain' cultivar sold by Plant Select http://www.plantselect.org/plant_details.php?comment=noww&plant_number=21 The picture doesn't really do this color justice: it's velvety and rich purple-violet-rose, a really scrumptious shade. I have no doubt this cultivar derives from the Sentinel area--they looked just like that...

But the thlot plickens! I got a pinch of seed there years ago and grew it, and the progeny were all various soft pinks, just like Mark's plant (and like the jucundum from elsewhere in the Draks). Since then I've grown a white flowered plant nearby that's related to these, and they've hybridized in my garden (see below), where they are very happy campers and bloom all summer and just generally delight me. I am anxious to get true jucundum from elsewhere in the Drakensberg to really compare and see what's up with this very good group of plants.

Intriguing info on Osteos!  Finally found a photo of O. jucundum taken in the garden June 2008, before being decimated by mice the winter of 2009.  Just checked, and about 5 strong growing pieces look like they came through the winter fine. :)