Last week I wrote about my visit to the Los Angeles County Arboretum in Arcadia. I mentioned that arboretums and botanical gardens are unique because of the ample space allotted to plants in order for them to reach their full potential.
At the Arboretum, there is no better example of this than a remarkable giant bird of paradise, the largest of its kind I have seen in more than 25 years of Los Angeles plant watching.
Giant bird of paradise (Strelitzia nicolai) grows at a moderate rate, its curving, hyperbolic trunks increasing in length about 2 feet per year and eventually reaching 30 feet or more in height. For flowers, it shows off husky birds with purplish black plumage and ivory crests with single extruding blue feathers but, even out of bloom, giant bird of paradise has a majestic presence that needs no flowery superlatives to be appreciated. All you have to do is look at it.
Want to simplify your life? If you allowed a multitrunked giant bird of paradise to develop in your front yard, you would not need any other plants to create an equatorial atmosphere. Every time you looked at your giant bird, you would be transported to a languorous tropical retreat. You would have a taste of Tahiti just beyond your front door throughout the year.
If you still wanted to underplant your architectonic, yet dull-colored, giant bird of paradise with complimentary and colorful botanical fare, orange cannas – with vivid flowers and bronzish burgundy leaves – would be the logical choice. Cannas are related to bananas, and to birds of paradise, heliconias and ginger, too, for that matter.
Although botanical classification is done strictly by flower characteristics, all of the above groups have leaves with a shape that is somewhere between a paddle and an ellipse.
Previously, I had never seen cannas that were taller than I but, at the Arcadia arboretum, I encountered a large collection of orange cannas that were more than 7 feet tall.
I also met up with a wonderful display of Heliconias. Gary Hammer, the iconic Valley nurseryman and international plant explorer, once told me that heliconias, sometimes referred to as lobster claws, “will grow in the Valley, in bright shade, needing a little more light than fuchsias.” Although indigenous to the warm tropics, certain heliconia species from higher altitudes, such as Heliconia spissa, Heliconia aurantiaca and Heliconia schiedeana, are hardy enough to handle average Valley winters.
Chinese dwarf banana (Musella lasiocarpa) is one of the most cold-hardy of the banana group. Its deep-yellow flowers, formed like artichokes, last throughout the summer. Chinese dwarf banana grows no more than 6 feet tall and, although it dies back each winter, reliably regrows from stout rhizomes with the resumption of warm weather.
At the Arboretum, adjacent the lobster claw and Chinese dwarf banana, is a spectacular giant Dutchman’s pipe (Aristolochia gigantea). Foot-long flowers, whose fragrance will remind you of lemon-scented furniture polish, are suspended from this vining plant. Growing up against an Arboretum greenhouse, frost-tender Dutchman’s pipe benefits from heat that warms the greenhouse during winter months.
I have frequently sung the praises of Peruvian lily (Alstroemeria hybrids) but had never seen an example of a parrot lily (Alstroemeria psittacina) before finding it at the Arboretum.
Parrot lily flowers are smaller, yet displayed in greater abundance, than those of its more commonly seen Peruvian lily cousins. Parrot lily can grow in more shade than Peruvian lily and would make an excellent perennial 3-foot-tall ground cover for minimally sunny exposures.
An orange monkey flower (Mimulus aurantiacus), of similar stature to parrot lily, would make an excellent comparable ground for full-sun locations.
The Arboretum is famous for its dawn redwoods. Dawn redwood (Metasequoia glyptostroboides), first discovered in a remote mountainous area of China in 1945, is a deciduous tree, unlike its evergreen redwood counterparts that grow in California. However, in the manner of California redwoods, dawn redwood is very long-lived, with a lifespan that eclipses 1,000 years, even if its mature height, of around 100 feet, is less than half of the 200-plus feet for which California redwoods are known.
Of all the plants I saw for the first time – and there were dozens – in the course of my Arboretum excursion, plume rush (Restio tetraphyllus) made the most profound impression.
At first glance, it looks like it could be a horsetail relation, except that it is more lush and moves gracefully in a breeze. I learned that this plant can grow in either moist or, once established, dry conditions. It is somewhat frost sensitive, however, and may be more sensibly grown in a container than in the ground.
Tip of the week
If you are wondering what to plant under sweet gum (Liquidambar styraciflua) or California sycamore (Platanus racemosa) trees, consider oak leaf hydrangea. This partial-shade perennial produces large panicles of white flowers that turn to pink as they age. Its flowers resemble those of California buckeye (Aesculus californica), a tree that is also in bloom at this time. If you want to see a California buckeye up close, you will find one growing at the bottom of the slope beneath the Nature Center in Franklin Canyon Park, just minutes from the intersection of Coldwater Canyon Boulevard and Mulholland Drive.