How to grow winter melon
Overview
Winter melon (Benincasa hispida) is a vigorous annual vine in the Cucurbitaceae family, grown for its large, waxy-coated fruit that can be stored for months after harvest. It thrives in heat and needs a long, warm season to reach full production, making it ideal for gardeners who want a high-yielding, space-filling crop.
Varieties
- Benincasa hispida 'Large Round' — Standard round-fruited type, reliable in AU/NZ conditions.
- Benincasa hispida 'Oblong' — Elongated fruit, easier to store and slice.
Soil Preparation
Prefers well-drained, loamy soil with pH 6.0–6.8. Enrich with aged manure or compost before planting; add a handful of lime if soil is acidic. Ensure good drainage to prevent root rot in wet periods.
Growing Guide
Sow seeds 2 cm deep in mounds 1.5 m apart after soil has warmed to at least 20°C. Space plants 60–90 cm apart in rows. Direct sow is best; transplant only with care to avoid root disturbance. Train the main vine up a strong trellis or let it sprawl over a 2 m wide area. Pinch out lateral shoots to focus energy on 2–3 fruit per plant. Keep soil consistently moist but not waterlogged, especially during flowering and fruit set.
Sowing
Sow seeds 2 cm deep, 3–4 per mound, thinning to 2 strongest after germination. Germinates in 7–14 days at 25–30°C. Direct sow is preferred; transplant only if using biodegradable pots to avoid root shock.
Care
Feed monthly with a balanced liquid fertiliser (e.g., 10-10-10) or side-dress with compost when vines begin to run. Mulch heavily with straw or grass clippings to retain moisture and suppress weeds. Prune to 2–3 main fruit per plant for best size and quality.
Companion Planting
Plant with corn, sunflowers, or beans to share trellis support and attract pollinators. Avoid planting near other cucurbits like pumpkin or cucumber to reduce pest and disease pressure. Marigolds and nasturtiums nearby help repel aphids and mites.
Common Pests & Risks
Aphids and two-spotted mites can cause leaf curl and stunted growth; control with neem oil or strong water spray. Powdery mildew appears in humid conditions; improve air circulation and apply sulfur spray. Cucumber beetles may damage young fruit; use row covers until flowering.
Harvesting
Harvest when the fruit develops a thick white waxy bloom and the skin is hard enough to resist a fingernail scratch, typically 80–100 days from sowing. Young fruit (10–15 cm) can be picked for stir-fries. Mature fruit stores for 3–6 months in a cool, dry place.
In the Kitchen
Use young fruit in stir-fries, soups, or curries; mature fruit is peeled and cubed for stews or candied. Store whole in a cool pantry for up to 6 months. The mild flavour absorbs strong spices well.
Troubleshooting
Yellow leaves: overwatering or nitrogen deficiency; reduce water and feed with liquid fertiliser. Brown edges: sunscald on young fruit; provide light shade. Fruit drop: poor pollination; hand-pollinate with a brush. Powdery mildew: high humidity; increase spacing and apply sulfur. Stunted growth: cold soil; wait for 20°C+ before planting.