By definition a Mallee is a multi-trunked Eucalypt often originating from a fairly arid part of Australia or where the environment is windy ,exposed or with shallow soil. The multi stems are thought to be an adaptation to the harsh growing conditions ,as wind blown leaves are able to collect around the base of the tree more readily, thus conserving soil moisture.They are usually smaller growing than other Eucalypts making them ideal for using in suburban gardens, courtyards and growing under power lines. The multi stems often give way to a single trunked specimen in these more favourable growing conditions. Herein lies a problem. Often they are tied to a stake "to make them grow straight" even though they have been "programmed" to make way for other stems and want to grow almost horizontally when young. This is particularly the case with Eucalyptus caesia This small tree is from the Mount Stirling Ranges and Murchison River district of Western Australia and occurs naturally on granite soils. The flowers are remarkable and are produced in bunches of three sometimes directly from the main trunk
While the upper stem bark is mealy white, the lower trunk has thin dark red bark which peels off in decorative little curls. I like to plant it in groups of three and it is complimented by underplanting with a tall evergreen grass such as Miscanthus transmorrisoniensis. I have seen it underplanted with Gaura lindheimeri which complimented the delicate airy pendulous branches of the tree.
My second Mallee is Eucalyptus curtisii , Plunkett Mallee. This small tree produces masses of creamy white flowers which cover all the ends of the branches in November. Needless to say it comes alive with all manner of insects and birds attracted to the blossom. The bark is satiny smooth to touch. It rarely grows straight up but twists and turns all over the place .
Another smooth barked specimen is the Port Jackson Mallee , Eucalyptus obtusiflora .As the common name implies ,it is a coastal plant adapted to thin Hawkesbury sandstone soils .The leaves are large ,thick and leathery able to withstand strong winds . The flowers occur from June to August . It would make an excellent low shrubby hedge in an exposed coastal garden.