How to create a drought-resilient garden in Melbourne

Melbourne's long-running Regional Office station recorded a mean January maximum of 25.9°C and around 648 mm of rain a year across 160 years of observations. Those averages hide the events that kill plants: on 7 February 2009 the same station reached 46.4°C, its highest reading since records began in the 1850s, beating the 45.6°C of Black Friday in 1939.

It is worth knowing that Melbourne has no single official rainfall figure. The newer Olympic Park station, open since 2013, averages around 575 mm a year and a warmer January maximum of 26.8°C. Different stations and different record lengths give different numbers, so treat any single figure as indicative.

The Millennium Drought, generally dated 2001 to 2009, remains the reference point for what a long dry period does to Victorian gardens. The Bureau of Meteorology notes that many parts of Victoria recorded their lowest rainfall on record over that twelve-year span, with a cumulative shortfall equivalent to two entire years of normal rain.

The Bureau and CSIRO's State of the Climate 2024 projects a further decrease in cool-season rainfall across southern and eastern Australia, and likely increases in the average duration of drought. Australia has already warmed 1.51 ± 0.23°C since national records began in 1910.

Practically, the interventions that matter are unglamorous. Improve soil structure so it holds water. Mulch deeply. Group thirsty plants together near the tap and put dry-tolerant planting furthest away. Water less often and far more thoroughly, so roots follow moisture downwards instead of sitting in the top few centimetres.

Victoria's Permanent Water Saving Rules have applied statewide since 2011: you may water by hand-held hose with a trigger nozzle, bucket or watering can at any time, but automatic systems may only run between 6 pm and 10 am. Design your watering around that window rather than treating it as an inconvenience.

Plant selection comes after all of this. Dry-country natives and Mediterranean species handle the dry season without irrigation once established, but they need sharp drainage through the wetter months, and several Mediterranean species have naturalised in parts of Australia — check state declarations before planting.