Get out your party hats, you blokes and sheilas, Australia Day is January 26!
For all of you who are not from "down under," it's sort of like our 4th of July — but different because Australia is still part of the Commonwealth, while the USA did that independence thing.
Different yes, but still a huge national celebration. Flags fly, businesses close, and there are plenty of parades, fireworks, concerts and beer. Since I write about gardening, my Australia Day celebration is about Australian plants that do well in southern Arizona landscapes. Indeed, I started this topic back in 2007, and am finally going to get past "A is for Acacia."
Much of Australia has alkaline soils like we have here, and seasonally dry periods, like us. There are also areas of high summer temperatures, like ours. This means that many Australian plants will do well in our landscapes. But not all of Australia is desert. Or hot. They have ski areas. The east coast is temperate, with acid soils. So only some Australian plants really thrive here. I am covering the ones you will commonly find in area nurseries.
How about a 40-foot tree that has a narrow form, provides little shade, has giant seed pods with tiny thorn-like hairs inside, and sheds leaves all the time? It's not that I don't like this tree, it's just that this tree is fine for very few situations, and those situations are almost never found in a homeowner's yard. Australian bottle tree (Brachychiton populneus) is good for narrow islands in streets and in other areas where a leafy green pole is needed.
Callistemons, the bottlebrushes, are another matter entirely. Small trees to large shrubs, they fit in most yards, flower profusely, and are great for attracting butterflies and hummingbirds.
For best floral display, treat bottlebrushes as you would citrus trees. This means fertilizer three times a year, water once every two weeks in summer, and acidify the soil. The plants are worth it. Like citrus, bottlebrushes are evergreen and can take reflected sun to part shade. The bonus is that they tolerate lows down to 15 degrees. For year-round bursts of glorious bloom, avoid pruning any of these, other than for basic shape when they are juvenile.
Callistemon citrinus (formerly C. lanceolatus), lemon bottlebrush, is the species most commonly found in yards. While it grows best as a large shrub, 10 to 15 feet tall and wide, it can be trained into a small patio tree. Vivid green leaves smell lemony when crushed, and are coppery colored when new. There are a number of cultivars.
Crimson bottlebrush (Callistemon phoenicus) is a newer introduction that can stand alkaline soils better than other bottlebrushes. Grows to eight feet high by six feet wide, with an open form, showing off its branch structure at all times, and thus often used as a background plant.
Stiff bottlebrush (Callistemon rigidus) is, well, stiff. And craggy looking. With narrow, almost pine-like leaves and reaching 20 feet high by 10 wide, it needs a special site to look right. Makes a great background plant to large mounding grasses, a combination that offers the multiple layers that most native birds prefer.
White bottlebrush (Callistemon salignus) has leaves that are willow-like, and willow-like are white underneath. The flowers are creamy white to yellow depending on the seed batch you get. Growing to 20 feet tall by 15 feet wide, this species makes a lovely small tree with a very dense crown. It can also be used as a tall hedge.
Weeping bottlebrush (Callistemon viminalis) is a great small tree with that weeping willow look. The species is fast-growing to 25 feet (or more) high and spreading to 15 feet, but there are numerous smaller cultivars. If you want this lovely patio tree, I advise shopping at a reputable nursery not a big box store. For example, C. viminalis "Little John" reaches the towering height of three feet and makes a lovely low shrub. "Captain Cook" reaches six feet tall, while 'McCaskillii' reaches 20 feet with a dense canopy and outstanding bloom.
Stay tuned to this newspaper for more Australian plants next Australia Day. Or maybe sooner.
Registrations now being accepted for spring gardening classes including "Design Your Own Landscape" "Winter Vegetables," and many more. Visit: oasisnet.org/Cities/TucsonAZ/Classes, and scroll down through the Wednesday classes, or call Oasis at 322-5627 for a catalog.