If you take a map of the world and draw a horizontal line through Los Angeles, you will eventually reach southwestern Australia. Any plant that grows there can grow here, too. The sea- bordering, southwest corners of all the continents, in fact, have Mediterranean climates that resemble each other.
Just as Australia has its distinctive fauna, from kangaroos to koala bears, its plants are similarly unique. Because of its geographic isolation, nearly all species of several notable genera — Eucalyptus, Grevillea, and Melaleuca, for example — are endemic to Australia, which means they cannot be found growing wild anywhere else.
Where winter gardens are concerned, there is a distinct advantage to planting Australian natives due to their foliar interest. Even when not in bloom, these plants are a sight to see.
Take dwarf willow peppermint tree (Agonis flexuosa ‘Nana’). Here is a ground cover with added value due to its special character traits. In winter, new growth is scarlet, chasing away the doldrums brought on by overcast skies, a bright foliar fire to dispel the gloomy, chilly weather. In addition, foliage is both fragrant and kinetic, swaying gracefully and wafting its perfume towards you with the slightest breeze.
Although its rate of growth is slow, dwarf peppermint tree is ultimately not so dwarfish after all.It may take a decade or more, but this plant will eventually reach six feet plus in height. Thus, you could plant it as a ground cover where there are taller species in the background with the understanding that, in the fullness of time, it could fill the area completely as a graceful, informal hedge. And then, again, you could keep it as low as you wished, with the understanding that each winter its new growth would take on a distinctive fiery glow.
Grass trees, long before they go arboreal, are stellar vegetative explosions which, if they happened in the far reaches of outer space, would go by the name of supernovae. First foliage may be golden but it will eventually turn dark green. The common Australian grasstree (Xanthorrhoea preissii) is exceedingly slow growing and will require 100 years to reach a height of three feet, with the oldest known specimens living for 600 years. In its junvenile state, prior to forming its characteristic black trunk, it displays an abundance of foliar spears, radiating in every direction like the tentacles of a sea anemone, that grab the attention of even those who are patently indifferent to the world of plants, except when it comes to eating them.
But even those who consider a plant’s value solely in terms of whether it can be chewed and swallowed or turned into an alcoholic beverage would display some interest in the grasstree. As a source of food and drink, grasstrees played an important role in aboriginal life. Parts of leaves and roots were eaten and seeds were pounded into flour. Beetle grubs and moth larvae would burrow through the grasstree’s accumulated thatch of dead leaves — comparable to palm frond thatch — only to be extracted and eaten either raw or cooked. Carpenter bees would make their homes in grasstree flower stalks, leaving behind deposits of honey. Grasstree flowers soaked in water yielded a delectable nectar for a sweet drink. Allowing this solution to ferment for three to five days would create a potent, lemony, and alcoholic potable to which smashed up ants might be added for extra flavor.
Grey cottonheads (Conostylis candicans) provide a fitting gray foliar contrast to the gold and green of grasstree foliage. Grey cottonheads are related to kangaroo paws (Anigozanthos spp.) and, like this other Australian endemic, grow from rhizomes and may be divided at the roots as a means of propagation.
Weeping acacia (Acacia pendula) is another study in gray, and its foliage is more pedulous than that of any other weeping tree. Weeping acacia is strictly ornamental, growing no taller than 25 feet and yet, in the manner of Acacias generally, tends to be short-lived. Pearl bluebush (Maireana sedifolia) possesses delicately crafted blue-gray foliage which, in the opinion of some, is more decorative than the foliage of any other plant and is highly sought after as a filler for floral bouquets.
Ashby’s banksia (Banksia ashbyi), in addition to its silvery sawtooth foliage, sports stout orange flower wands that may also be detached for dry flower arrangements.
Two local nurseries with a wide selection of Australian natives are San Marcos Growers and Australian Native Plants Nursery. The former is a grower but you can find retail outlets for their plants by visiting smgrowers.com. The latter, located in Ventura, sells directly to the public by appointment and may be contacted at 800-701-6517 or found online at australianplants.com.
Australian natives, like California natives, aside from their beauty, are brought into gardens due to their drought tolerance. Yet, even today, there are lawn grasses that are highly drought tolerant, especially when properly maintained. And let’s face it, if you want to play croquet or badminton or whiffle ball with your kids in the backyard, and have a nice cool surface to fall on, there is no substitute for a lawn.
I just learned about a new advancement in sprinkler technology that claims to save lots of water, up to 50% of the water applied through conventional sprinkler systems. Dubbed the genius sprinkler, the technology involved was developed by Gary Klinefelter, an inventor who had more than 30 inkjet printing patents. Klinefelter’s new technology was an answer to this question: “If an inkjet printer prints ink in controlled patterns and shapes on a surface, could a sprinkler apply or ‘print’ water in a similar fashion?” Klinefelter’s response, after three years of product development, was a resounding yes. He can water a plot up to 900 square feet in size with a single sprinkler, where the pattern in which water is sprayed conforms exactly to the shape of the plot. The sprinkler is a 5 inch tall rotary pop-up that contains 14 nozzles distributing water in 14 digitally programmed streams. Moreover, the genius sprinkler can be programmed to water so precisely that its streams will reach up to the edge of an adjacent sidewalk or street curb without going beyond that edge. Programming and monitoring genius sprinklers can be done with an iphone and controlled at long distance.
Aside from the water savings produced, another advantage of the genius sprinkler is the savings in material and labor when it comes to installation. Conventional systems place sprinklers along the edges and at the corners of a plot, requiring a considerable amount of pipe and labor to install as compared to a genius sprinkler, where a single length of pipe emanating from the main line to the middle of the plot is sufficient. You can learn more about genius sprinklers at irrigreen.com.
Tip of the Week: A major caveat when growing plants native to southwest Australia is to be careful when it comes to fertilization with phosphorus. This mineral is absolutely toxic to some of these plants and it would be wise to investigate phosphorus sensitivity of any Australian species prior to planting it. Where you have no choice but to plant in soil where phosphorus has previously been applied, it has been shown that ample fertilization with iron may blunt or entirely eliminate phosphorus’ potentially deleterious effects.