May in Perth is autumn, the prime window for cool-season crops across much of Australia. Here’s exactly what to sow from seed, plant as seedlings, and harvest this month in a mediterranean/temperate climate, tuned to Perth’s frosts and temperatures, not a generic national calendar.
Typical Temps
9-35°C
winter low to summer high
Frost
Frost-free (coastal), rare light frosts in hills July-August
Climate Zone
Mediterranean/Temperate
Western Australia
Frost watch: The Swan coastal plain is frost-free. Only the Perth Hills and inland market gardens get occasional light frosts through winter. See frost dates for every city →
Perth's dry summers require drip irrigation or soaker hoses rather than overhead watering, conserve water and reduce fungal disease risk simultaneously.
Unlike east coast cities, Perth's best tomato planting window is actually August-October for a summer harvest, with a second planting possible in late February.
Perth's Mediterranean summers are too hot and dry for most leafy greens, focus on heat-tolerant herbs (rosemary, thyme, oregano) and water-efficient crops like sweet potato in summer.
The wet season (June-August) provides free watering, so winter is an ideal time to establish new raised beds and plant heavy feeders like brassicas.
From the makers
This calendar tells you what's possible in May, Plant Planner tells you exactly how many of each crop to grow for your family, how to arrange them in your beds, and sends reminders so you never miss a window.
In May, Perth gardeners can sow Garlic, Broad Beans, Peas, Snow Peas, Broccoli, Cauliflower and more from seed, and plant out Broccoli, Cauliflower, Cabbage, Leek, Onion as seedlings. Perth sits in the Mediterranean/Temperate climate zone, so these picks are timed to local conditions.
May falls in autumn, the prime window for cool-season crops across much of Australia. In Perth, expect winter lows around 9°C and summer highs near 35°C. The Swan coastal plain is frost-free. Only the Perth Hills and inland market gardens get occasional light frosts through winter.
May is generally not the ideal window for tomatoes in Perth, they're a warm-season crop sensitive to frost. Use May for the season's recommended crops above, and check the Perth calendar for the best tomato-planting months.
In a Perth garden, May typically brings harvests of Tomato (last), Broccoli (early), Lettuce, Asian Greens, Silverbeet, Radish. Actual timing depends on when each crop was planted.