Weelllll...... some of the more marginal tropical plants simply look TOO tropical for a PNW garden. They look out of place; better suited to a warmer, less woodsy/treed climate. And we are restricted in selection as well. As for palms, the commonly seen ones are windmill palm (Trachycarpus fortunei), fan palm (Chamaerops humilis) and the odd Butia capitata. For bananas, you are pretty much limited to Musa basjoo and sikkimensis......and they will need winter protection. And some species of Bambusa are hardy here.......the alternative is Fargesia (for clumping) or most runners (if you are brave enough).

I'd consider something that is very cold hardy yet has a lush, tropical look, usually meaning large foliage - gunnera, petasites, aroids if you have a shady area, rogersia, Melianthus, Fatsia japonica. Ricinus for an annual show. Catalpa or paulownia for trees; also Magnolia macrophylla, Albizia julibrissin. Even some of the rhodies can have a semi-tropical look with very big leaves and very showy flowers.

These all seem to have a better affinity and fit in a PNW landscape than do the other, more tropical tropicals, which just seem to look out of place unless very carefully designed into the landscape.

Hardy Japanese banana has been grown outdoors in Vancouver for decades. One planting we noticed just north of UBC we were told by the man who came to the door was present when he started working there in the 1950s. I doubt this planting was being covered each winter the whole time, but we didn't ask.

(I have been told by a zonal denial specialist down here that the trick is to get starter plants of the banana through their first winters, with them being hardy after they get up to size).

However, Bellingham seems to be colder than Vancouver, presumably due to some detail of how the cold air in winter comes down the Fraser River and where it goes - Bellingham and vicinity is probably about the worst lowland area in western WA for you to settle in with your particular interests. You would do much better with the types of plants you like farther down the Sound, away from the Fraser Outflow - you can see the general pattern of winter conditions here by looking at the western WA Sunset Climate Zone map in the Sunset Western Garden Book.

People with central Puget Sound properties right on the water, such as in the Fauntleroy area of Seattle and areas west of there, experience California mild conditions for long periods of time. When I belonged to the local Rhododendron Society chapter during the 1970s one member who lived near the Fauntleroy ferry dock would come to meetings with flowering samples of rhododendrons in his garden that were kinds ordinarily seen much farther south, in northern California for instance.

Minimum temperatures on individual planting sites are critical to success with a zonal denial plant collection. There are favored properties that may perhaps seldom drop below 15-20F and others a few miles away that sometimes get near 0F. For instance during the last decimating winter, in 1990 12F was reported from a place near the water in northwest Seattle and 2F was claimed for another, at roughly the same latitude, near North Seattle Community College, over by I-5. Such differences decide whether or not borderline plants can be kept going - there is a lot of stuff that checks out at about 10F or so.

Two Pacific Northwest retail nurseries with outdoor settings that are planted to make it look utterly like you have been instantly transported thousands of miles to the south are Jungle Fever Exotics in Tacoma and Cistus nursery near Portland.

http://www.cloudforest.com/cafe/palms/ Try this link, there are more people on this board that like to challenge the limit of plants than on this board.