1 Unwrap & Soak

Carefully unwrap your slips and place the roots in clean water for 24 hours to rehydrate and reinvigorate them.

2 Choose the Spot & Plant

Choose a sunny, sheltered position with free-draining soil. Kūmara need warmth and do not tolerate frost, so plant after the last frost in late spring or early summer, once the soil has warmed to around 18 °C.

Prepare the soil deeply and incorporate compost or well-rotted manure. Kūmara do especially well in a slightly sandy, fast-warming bed. Raised mounds or rows about 30 cm wide by 20 cm high can help with drainage and warmth.

Lay each slip horizontally in a shallow trench along the top of the mound or row. Bury the roots and lower stem, leaving only the top few leaves above the soil. Gently firm the soil and water well.

Space slips about 30 cm apart, with rows approximately 60–80 cm apart.

3 Watering & Care

Water well after planting and keep the soil evenly moist for the first 2–3 weeks while the slips establish.

Once they are growing strongly, reduce the frequency of watering but water deeply. Kūmara dislike waterlogged soil.

Kūmara need plenty of warmth and sunlight. Avoid high-nitrogen fertilisers, which can encourage excessive leafy growth at the expense of tubers. A balanced organic fertiliser or seaweed tonic can be used as needed.

Lift or gently turn the vines over every few weeks while they are growing to prevent them rooting into the soil along the stems. This helps keep the plant putting its energy into the main crop.

Keep the area reasonably weed-free and consider mulching with straw or compost to conserve moisture and moderate soil temperature.

4 Harvest

Expect to harvest after approximately 120–150 days (4–5 months), ideally before the first frost. Leaves may begin to yellow as the crop matures.

Choose a dry day if possible and carefully lift the tubers with a garden fork, taking care not to damage the skins.

After harvesting, allow the tubers to dry and cure before storing them in a cool, dry place. Avoid bruising or damaging the skins, as this can reduce storage life.