South American plants for Vancouver

Happened to walk by the Gateway to Chile for the first time yesterday. The leaves of the majority of the new plants were all or partly brown, and/or dropping off. There was one feather palm inside a cage which would have been put on to protect it from the cold last month. However, it looked as though it may have been brown also - it was not near a path so I did not get a close look at it.

 

When you're considering what will actually succeed in the Northwest, it seems apparent that you DO need to consider one climate variable above the others, that being the extreme minimum temperature. There are all kinds of plants native to places that have cooler year round temperatures than Seattle or Vancouver, frost on every month of the year, etc.; but still aren't hardy here. Most of them come from the cooler parts of Australia, New Zealand and (especially) South America. Parajubaea torallyi would be a fine example of such a plant. It is native to 11,700' in the Andes of Bolivia at the upper end of its range, a climate that is cool year round and experiences frequent light frosts. But despite having been tried quite a bit along the west coast it starts showing frost damage in the low-mid 20s F.

Actually Jubaea is hardier than Parajuabea, having nothing to do with the climate in which it originates but it is simply built into the genetics of the plant. In general it is still not quite hardy enough for Pacific Northwest gardens without protection for many years. Jubaeas at the Arboretum might have been a good investment had the Arboretum been prepared to protect them from what we all expected to be one of our coldest winters - I haven't checked them out yet.

As for Polylepis, Cistus Nursery near Portland has a specimen in their garden, an unknown species collected from Tafi del Valle, Argentina. Sean Hogan has suggested he thinks it might be P. australis but I'm not so sure about that, since it looks quite different from the P. australis I have grown from Chiltern Seeds. P. tarapacana would have to be hardy since I read a journal paper in which lab tests found the leaves to be able to withstand -17C before injury occurred.

Other South American plants that have done well for me over the years include Pseudopanax latevirens, Maytenus boaria, Luma apiculata, Gunnera chilensis, Myrceugenia ovata var. nanophylla, Prumnopitys andina, Fitzroya cupressoides, Podocarpus salignus, Eucryphia cordifolia and Embothrium coccineum.

 

>When you're considering what will actually succeed in the Northwest, it seems apparent that you DO need to consider one climate variable above the others, that being the extreme minimum temperature<

Ding! A great many kinds of plants that "ought to grow here" have been tried at the Seattle arboretum and elsewhere over the years, only to be lost when - sooner or later - it got too cold for them. The longer I have looked the more apparent it has become that you see certain plants over and over in the general landscape because (in part) those are the ones that are able to persist under our conditions. Including our winter conditions.

I saw one palm in the Gateway to Chile planting with a cage around it, think the leaves may have gone brown. No sign of the grove of tall ones, with trunks shown in the artist's rendering.

 

I'm going to add to this thread as I've found out some additional information through some digging about the climate of Southern Patagonia and Tierra del Fuego.
First off, the above bolded statement is completely FALSE. If it were true, then you would be able to grow the same subtropical plants in Vancouver as you could in Atlanta, Georgia and Dallas, Texas which is not the case at all. They all have roughly the same minimum temperature every winter.
Secondly, I did some research by contacting a meteorologist in Argentina to find out some information. I was curious to find out how many days a year weather stations in Southern Patagonia and Tierra del Fuego (in towns like Ushuaia, Rio Gallegos, Rio Grande etc.) have on average where the temperature never rises above freezing. I know this seems to be a major factor in determining survival in the PNW for some hardy exotics from the Magellanic subpolar forests of Southern Argentina (I hesitate to call them subtropicals cause they aren't) and NOT ONLY the minimum temperature reached. Now it seems the Argentinian meteorological service does not collect data on this climatic factor most probably because I was told "there are not many places in Argentine territory where this happens, so it's not seen as important." However, despite this, he was able to look over some weather records and give me a rough estimate of 2-3 days per year on average for the coldest communities like Rio Gallegos, Rio Grande and Ushuaia where the temperature does not rise above freezing.
This is well within the norms of the coastal areas of the PNW most definitely and I still see no reason as to why species from the Magellanic subpolar forests cannot THRIVE here. We have far better growing conditions overall and it should be a peace of cake for them as we also get warm enough summers to actually cause them to grow much more quickly.
Keep in mind I'm NOT talking about species like Jubaea Chilensis which is native to much further north in Chile and Argentina where the climate is much more akin to Northern California and not like the PNW. It stands to reason that it would struggle here because the climates are not the same.
I'd love to be able to grow exotic plants like those found in the Subpolar Magellanic Forests... Drimys Winteri, all the Nothofagus species... should perform magnificently here.