Growing Sweet Potatoes in Australia

A Truly Australian-Friendly Crop

Sweet potatoes (Ipomoea batatas) are one of the most productive, nutritious, and heat-tolerant vegetables you can grow in Australian conditions. Unlike regular potatoes, which struggle in summer heat, sweet potatoes love it. They are low-maintenance once established, cover ground prolifically (suppressing weeds in the process), and produce a calorie-dense harvest that stores for months.

Climate Requirements

Sweet potatoes are tropical and subtropical plants that need a frost-free growing season of at least 4–5 months. They thrive in Queensland, Northern NSW, and northern Western Australia. In Sydney and Perth they grow well but production is reduced. In cooler climates like Melbourne and Adelaide, they can be grown in the warmest microclimates with careful timing, starting slips indoors and planting out only after all frost risk has passed.

Growing from Slips

Sweet potatoes are grown from slips — rooted shoots taken from a parent tuber — rather than from seeds or the tuber itself (unlike regular potatoes). To produce slips: place a sweet potato half-submerged in water in a warm, bright position. Shoots will emerge in 2–4 weeks. When shoots reach 10–15cm, twist them off and place in water until they develop roots (1–2 weeks), then plant out. Alternatively, purchase slips from garden centres in spring.

Planting

Plant slips in well-drained, sandy to loamy soil in full sun. Sweet potatoes do poorly in heavy clay — if your soil is heavy, grow in raised beds with a well-drained mix. Plant slips on a slight ridge or mound, spacing plants 30–40cm apart in rows 80cm wide. The vines will spread aggressively — allow at least 1.5m between rows, or let vines sprawl where they will. Do not over-fertilise with nitrogen — this produces masses of lush foliage but few tubers.

Care and Harvesting

Sweet potatoes need minimal care once established. Water during establishment and during dry periods, but they are remarkably drought-tolerant once the vines are running. Harvest when the leaves begin to yellow and die back (usually 4–5 months after planting), or when frosts are forecast. Dig carefully — tubers can be surprisingly large and spread widely. Cure harvested sweet potatoes at 28–32°C and high humidity for 1–2 weeks to heal any wounds and convert starches to sugars, dramatically improving flavour and extending storage.