My friend Steve has urged me to periodically write about my experiences in the Denial Zone…so here’s a little something: We all know you can only go so far with the whole tropical thing in Portland if you’re not going to invest in a greenhouse. Those of us who try to mimic the tropical look realize that we have to seek out the temperate and a few sub-tropicals that give us that ‘feel’. Bold foliages are key. Architectural plants, and just as important strong foliage contrast. This is not the place for subtlety. Strappy, fuzzy, split and dissected, compound pinnate and palmate, glossy, drip tipped, bold variegation and wild patterns…over the years observant nurseryman and plant hunters have brought us a smorgasbord of unusually foliaged plants. Plant breeders have pushed the limits crossing hardy species in ways that mimic their tropical cousins, I’m thinking Hibiscus here. But still there are certain plants, certain forms and silhouettes, that are hard to replace.
Palms are one of these. Many of us grow various palmate forms like genus Trachycarpus, T. fortunei, most commonly, while others have used T. wagnerianus, T. takil and T. princeps. There are many others but of unproven hardiness. Another form of Palm are those with costapalmate fronds, of these I have a Sabal minor doing fine at home slowly getting bigger in the ground for the last four years, (It’s more than ten years old. I’m of the age now where I just say something is ten years old because it’s easier than checking. It may actually be 12-15.) and a Sabal x ‘Birmingham’ I have high hopes for probably destined for a few more years in the pot before I try it out in the ground. (The genus Sabal includes the Palmetto Palm native to the coastal southeastern US. They tend to be slower growing than Trachys, preferring more heat, often with larger more deeply segmented fronds. For those of you who don’t know, costapalmate are intermediate between palmate and pinnate. The stem extends into the frond where the segments separate and fan out. This extension may be slight as it is in Sabal minor. Instead of having the segments radiating evenly from one point at the base, the ‘base’ is slightly elongated stretching it as if it were briefly considering being pinnate. A casual look might leave the observer thinking that something is slightly off with what appears to be a palmate leaf.) Perhaps others will be found growing in the extremes of their home ranges that can take zn7 and 8 consistently with smiles. I planted the aforementioned Trachys over the last several years in and near Waterfront Park’s bowl. (Actually, the T. princeps is new this spring. Cross your fingers.) They are consistent and durable performers…even through last winter.