MISCALLANEOUS EXOTIC PLANTS

This write-up may seem a bit incongruous, but it is simply a left-over piece from the old edition of this web page.  The collection has expanded so much since it was originally written, that this essay is not particularly relevant any more as a reflection of what is in the garden.  Some of these plants are pictured in the photo gallery.

This is such a broad subject, I am going to have trouble narrowing it down, so I guess my main purpose here will be give a quick taste of what we are growing and what we are interested in on a very general level, rather than going into a whole lot of detail about each.

I'll start with hardy bananas, which technically aren't trees.  Musa basjoo, the Japanese hardy banana, has bacome quite popular among palm society members and others, and has already proven that it is obviously quite well adapted here and can be considered fully hardy if treated as a dieback perennial.  It is indeed an honest-to-goodness banana tree capable of growing huge (8') leaves, but the fruit is not considered edible.  If a really huge specimen is desired, then the pseudotrunk must be protected with mulch so it will not freeze all the way back to the ground over the winter.  Other hardy bananas worth growing include Musa hookeri/sikkimensis, a recent introduction; Musella lasiocarpa, Musa velutina and Eneste ventricosum which seems to be quite popular as an annual in cooler climates.  Bananas do not like clay and we must grow them in raised beds.  I am not aware of any edible fruiting bananas that will thrive in our cool climate.

How about Cordylines?  Most of us have probably seen C. australis, which is found sold in nurseries all over the place as "Dracena indivisa" or "Spikes Dracena" (a very misleading name, I might add), and used as summer bedding where if not killed back by frosts (they are hardy to about 10 - 15°F/-9 to -12°C) they will eventually grow into very impressive, exotic-looking big trees with trunks even as far north as Tofino, British Columbia.  But there are other Cordyline species worth growing, including C. banksii, a clustering species, and especially the beautiful C. indivisa, which, contrary to popular belief, is actually about as hardy as than C. australis and much less heat-tolerant with almost alpine requirements.  Perhaps even more intriguing is the completely unrelated Richea pandanifolia from Tasmania, and the similar Dracopyllum traversii from New Zealand, just two examples of a group that is very much worth trying in the Pacific Northwest.  Unfortunately the seed has a very short shelf life and the plants have little tolerance for warm temperatures, so it may be a while before these are made to grow here.

Besides the Cordylines (and of course tree ferns), some other favorite New Zealand natives include Phormium, Hoheria, and some interesting Cortaderias (related to pampas grass).  There are also Pittosporums, particularly P. crassifolum and P. tenuifolim, both of which are hardy enough to look good in the Pacific Northwest most of the time.  Metrosideros species are probably among the most beautiful trees I have ever seen pictures of; in bloom they resemble a giant bright red cloud on the horizon! M. excelsa is reasonably well known in California but it is cold-tender--the best species to try up here is probably M. umbellata.  Sadly, they are slow-growing and take up to 30 years to flower!  New Zealand has many other wonderful trees such as Sophora tetraphera, Fuchsia excorticata and Pseudopanax sp. that we have now begun growing.

Oaks are also of interest, especially evergreen oaks.  We have perhaps 30 or so species (mostly evergreen), my favorite of which (so far) are Q. suber, Q. kellogii and the native Q. garryana.  Q. fusiformis should be of interest as one of the cold-hardiest evergreen broadleaf trees, having withstood -20°F (-29°C) undamaged.  We have also started growing a large number of Mexican and Southwestern oaks such as Q. pacifica, Q. polymorpha, Q. john-tuckeri, Q. hypoleucoides, etc.  Related to the oaks are Nothofagus species that form extensive forests in temparate areas of the Southern Hemisphere.  They are attractive at all stages of growth, and grow very rapidly to form beautiful large trees, some evergreen.  The evergreen N. fusca is probably my favorite so far, and I also have the deciduous N. procera which has beautiful fall color.  Also reasonably hardy are N. antarctica, probably N. cunninghammii, N. dombeyi, N. gunnii, N. obliqua and N. solandri to name a few.

We also have quite a few interesting vines, ranging from a small collection of passion vines (Passiflora), not all of which are hardy, to grape relatives such as Cissus incisa and Vitis coignetae which looks breatktakingly magnificent climbing up a douglas fir.  I am trying to train the beautiful Parthenocissus henryana up our big redwood tree.  We are also trying some herbaceous vining plants such as Bomarea, and some edibles such as Actinidia.  I'm also optomistic about Ficus pumila which survived last winter in a shletered spot.

The garden also contains some interesting birches, maples and various groundcovers and ferns.  My favorite maple is Acer tegmentosum, which looks a lot like A. davidii but with larger leaves, and I have to admit (even though it is blasphemous to most hard core exiticists) I really like our native A. macrophyllum a good bit.  Albizia julibrissin, the silk tree, has been a longtime favorite, and we are growing dark-pink and white flowered forms.  We also have a birch-bark cherry, Prunus serrula, as well as Erica arborea which I will eventually take cuttings of to make a forest of them.

I'm also interested in alot of South African flora, particularly the Aloes and the Proteaceae, and we are just beginning to try a good number of them up here.  I can highly recommend Aloe striatula (which should be hardy here), A. ferox, Leucodendron 'Pacific Sunset', L. salicifolium, Leucospermum tottum, Protea subvestita, P. eximia and quite a few others.  On the subject of Proteaceae I should also mention the Chilean Embothrium coccineum, which has white and yellow forms; and the beautiful Chilean Lomatia species I have yet to find a source for which put the modest L. myricoides to shame.

We are also trying out over 200 species of cold-and-wet-hardy cacti and succulents.  I have a rapidly expanding collection anxiously awaiting my completion of a well-drained raised bed for them, plus a bunch of our native Lewisias.  So far we have not ventured beyond Opuntias and Trichocereus in the cacti department (although we did try to germinate Maihuenia with no luck), and many of my other succulents are South African mesembs (ice plants) or Agaves. Recently I have become intrigued by the possibility of growing cold-hardy bromeliads, and have begun starting lots of Puyas, Hetchias, Aechmeas, Dyckias and Griegia in the greenhouse.  Fascicularia bicolor is now going into its second winter in the ground.

Finally I should mention the bamboo collection.  So far we have over 30 species, including Phyllostachys heterocycla pubescens, the moso bamboo; and three Chusqueas.  The smaller bamboo Sasa palmata is indespensable erosion control on steeper areas.  We are especially interested in mountain bamboos and large timber bamboos, as these seem to have the greatest effect of "exotica" in the landscape, and have not been trialled as extensively in our region.