When to Plant Sweet Potato in Brisbane — Subtropical Guide

Sweet Potato

Photo: Wikimedia Commons

Sweet potatoes are a warm-season, frost-tender crop grown from vine cuttings (slips), not seed. They are highly productive in warm Australian climates, with a single plant producing 2-5 kg of tubers. Beauregard (orange flesh) dominates Australian production. Tropical and subtropical zones are ideal; temperate growers need warm microclimates and season-extension techniques.

How to Grow Sweet Potato in Subtropical Australia

When to Plant

Plant September-January. Slips need soil above 18C. Harvest February-May (4-5 months after planting). In SEQ, planting from October to December is safest.

Soil
Well-drained, loose, sandy loam. Avoid heavy clay or waterlogged soil. Do not over-fertilise - rich soil produces excessive vine growth at the expense of tubers. Slightly raised mounds or ridges improve drainage and warming.
pH Range
5.5-6.5
Sunlight
Full sun (minimum 6-8 hours). Heat-loving crop - the more warmth the better.
Spacing
35cm apart, 100cm between rows
Watering
Water regularly during establishment (first 3-4 weeks). Once vines are growing strongly, reduce watering. Sweet potatoes are surprisingly drought-tolerant once established. Excessive watering encourag

Companion plants: Beans, Corn, Sunflower

Avoid planting near: No significant antagonisms, but vines will smother nearby low-growing crops

Subtropical Growing Tips for Sweet Potato

Recommended Varieties

  • Beauregard
  • Northern Star
  • Kestle
  • Orleans

Key Challenges

  • Weevil pressure from November onwards
  • Frost risk for late-harvested crops
  • Vine growth can be excessive in rich soil

Pro Tips

  • Plant slips October-November in SEQ for best results
  • Keep soil mounded over developing tubers to exclude weevils
  • Do not over-feed - lean soil produces better tubers

Harvesting Sweet Potato

When ready: Foliage begins to yellow (4-5 months after planting). Leaves may show autumn colour change. Scratch soil near a plant to check tuber size. In frost-prone areas, harvest before first frost as frost kills vines and can damage tubers.

How to harvest: Cut back vines first. Use a garden fork inserted 30-40cm from the plant base to loosen soil. Lift very carefully - sweet potato skin is thin and damages easily, and wounds lead to storage rot. Sort into damaged (use immediately) and undamaged (for curing and storage). Do NOT wash before curing.

Get the Full Interactive Guide

Open the interactive planting dashboard with real-time weather, all pest alerts, and garden tracking.

Join Garden Buddy for premium features: disease management, seed saving, preservation guides,.