Australian plants shine in winter
Marin basks in a Mediterranean climate characterized by warm, dry summers and cool rainy winters. This same climate is only found in five places: southern Europe, northern Africa, southern Africa, Chile, and southwestern Australia.
With recent droughts and limited water supply, many Marin gardeners have discovered the easy-care selection of plants from southwestern Australia, which are perfectly at home in our climate. As an added bonus, many are drought tolerant and deer resistant. And there are so many interesting ones available! There are 20,000 species of plants native to Australia, thanks to its vast size and temperate climate. As a point of comparison, there are 1,679 species of plants native to Marin County, according to Marin Flora, and 5,800 native to California, according to The Jepson Manual: Higher Plants of California.
Some Australian plants have become invasive pests in California. For instance, eucalyptus is listed as an "invasive non-native plant that threatens wildlands in California." The California Invasive Plant Inventory also lists Australian saltbush, Atriplex semibaccata, as invasive. Growers, horticulturists and nurseries must act with diligence and concern to prevent the import of Australian plants that may become pest plants here.
Where to see Australian plants
A visit to an Australian garden provides an up-close view of how these enticing plants can fit into your landscape. Here are some places to consider visiting:
• The Falkirk Cultural Center in San Rafael, where UC Marin Master Gardeners planted an Australian garden in 2008. Several species of acacia, grevillea, kangaroo paws and Australian mint bush are thriving there today.
• The Arboretum at UC Santa Cruz, with 30-40 acres devoted to Australian plants and an estimated 2,000 species, forms, or cultivars. Since 1978 the Arboretum has tested several hundred species of Australian imports, many of which have now been introduced into the nursery trade.
With so many spectacular Australian plants to choose from, it’s difficult to describe just a few. But here are some popular selections you may want to consider for your own garden from Down Under:
• Banksia are evergreen shrubs or trees. They grow in full sun with moderate water, and good soil drainage is required. The spectacular, cylindrical clusters of flowers give way to woody seed cones. The foliage varies by species. Plant size varies from low, prostrate species, to shrubs ten feet tall, to trees that reach 30 feet or more.
• Anigozanthos are perennials with erect, sword-like leaves. Their fuzzy tubular flowers, divided and curved at the tips, give them their common name, kangaroo paws. They grow in full sun with regular water. Foliage clumps can spread from 1 to 3 feet. Kangaroo paws prefers sandy soil, but will do well in loose, light soil with good drainage.
• Protea are evergreen shrubs with unusual and beautiful flower heads. The flower is actually a tight cluster of tubular flowers surrounded by colorful bracts. They make wonderful, long-lasting cut flowers. These plants may not be easy for the novice to grow because they are fussy about growing conditions. Protea demand good drainage, and some prefer acid soil. Protection from wind and good air circulation around plants is also important.
• Grevillea ‘White Wings’ are perfect for steep slopes with low water. These shrubs get to be substantial (7 feet x 8 feet), and have lovely colored stems, prickly leaves and abundant white fluffs of spiderish flowers. There are many types of Grevillea, and most are easy to grow and attract hummingbirds.
• Acacia: While there are three acacia species that are allergenic and can be invasive (avoid Acacia dealbata, Acacia baileyana, and Acacia cyclops), there are over 1,000 species that are not, and many are gorgeous. For example, Willow Wattle (Acacia iteaphylla) makes a great screen or low windbreak. It grows to 8-12 feet high and 10-15 feet wide, with narrow, gray green leaves and pale yellow flowers in late winter to early spring. Snowy Willow Wattle (Acacia boormanii) is also excellent for screens or windbreaks, growing 10-15 feet high and 6-15 feet wide, with gray-green leaves, and fragrant, bright yellow flower puffs at the branch ends in winter to early spring. River Wattle (Acacia cognate) grows into a graceful weeping tree, 15-25 feet high and wide, with narrow, drooping bright green leaves up to 4 inches long, and creamy yellow puffs flowers in the spring.
If you're looking for something different that is drought tolerant, colorful and exciting, try some Australian plants for your garden.
Original article by Katie Martin for the Marin Independent Journal
Edited for the Leaflet by Julie McMillan
Photos by Gail Mason