New Zealand - sub-tropical zone

Growing Sweet Potato/Kumara

(Ipomoea batatas)

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
                P P P  

(Best months for planting Sweet Potato/Kumara in New Zealand - sub-tropical regions)

  • Harvest in 105-120 days
  • Shoots or cuttings (Slips). Sow seed at a depth approximately three times the diameter of the seed.
  • Best planted at soil temperatures between 17°C and 35°C.
  • Space plants: 40-60cm

Frost tender Sweet Potatoes require a long warm growing season. Plant in free draining loose soil . Fertilise before planting but no more when the plants are growing as it will encourage vine growth. They will go for miles and you’ll get no tubers. If they do start spreading, lift the vines off the ground to prevent them rooting.

Mound up the soil about 20cm (8 in) before planting Let the plants die down, (leaves die or turn yellow) before harvesting the tubers. Dry them in the sun for a few days . then store in a cool dry place for up to five months.

Culinary hints - cooking and eating Sweet Potato/Kumara

Use mashed, boiled, roasted, baked or fried. Or use in soups, pies, casseroles, curries and salads.

Your comments and tips

01 Mar 15 Bruce Gare (New Zealand - cool/mountain climate)
can anybody tell me if you can grow kumara in Canterbury South island
10 Mar 15 Olmec Sinclair (New Zealand - temperate climate)
Bruce, I know kumara were grown in Kaikoura by Maori (no tech.) and my mother-in-law has attempted some there this season.... the plants look good. Might depend on where you are, what tricks you can employ to make it work. Maori had some techniques for raising soil temperatures like adding charcoal to make soil darker, absorb more solar. I am interested in trying here in north canterbury
06 Apr 15 Lorna Warrington (New Zealand - sub-tropical climate)
We have a barrel compost bin and threw a kumara in it with the potato peelings. The Kumara has grown but we don't know when to pull it up. The foliage is still growing quite well and shows no sign of stopping. When do we pull it up to see if we have any produce please?
23 Apr 15 Maxine Stewart (New Zealand - sub-tropical climate)
There is a type of kumara called "Rubicon" which I would love to source if that's possible. It's dark purple, both the skin and the flesh, and has a rich and delicious flavour. Does anyone know of it please?
02 May 15 Toni Paton (New Zealand - temperate climate)
I have just harvested my first crop of kumara {in Hamilton} and have found that I have lifted them a little early. I did some research and they are much like potatoes in that the foliage either dies off or turns yellow when they are ready. While we got some decent sized ones there were a lot of small ones. I suggest leave them as long as possible. We got some seedlings started from peelings that sprouted in the compost, and from some that had grown on the tuber we bought from the supermarket, so once you buy a kumara you have the potential to grow them. I lived in the Gold Coast and tried growing them in a bucket with potting mix. They were growing fine but I returned to NZ and have no idea how they turned out.
11 Jul 15 Diego (New Zealand - temperate climate)
Hi, I Want to know Where get seed of Kumara in Christchurch or Akaroa Thanks
26 Sep 15 Henry Ang (New Zealand - sub-tropical climate)
Hi I was wondering if purple sweet potatoes are available in New Zealand. If I can get them as seeds or tubers?
02 Oct 15 jenni (New Zealand - temperate climate)
I am having a go in South Canterbury. I sat a kumera in a small preserving jar so only a portion was wet. It grew roots there and lots of shoots at the top. The shoots did not sprout roots until I put the kumera into a larger container so that the water covered the base of their stems. Now there are lots waiting to go in to the hot house.
13 Nov 15 Marg Lloyd (New Zealand - cool/mountain climate)
Yes you can grow Kumera in Canterbury.I got a huge crop while living at Winchmore just west of Ashburton.I planted rooted shoots and they grew well
25 Nov 15 Anna Holmberg (New Zealand - temperate climate)
I grew plants from a store bought kumera last year and planted them and got a good crop , but the kumera had virtually no flavour , and I was wondering if you knew why that might be . Thank you .

Post a comment or tip about Sweet Potato/Kumara

Where are you?

All comments are reviewed before displaying on the site, so your posting may not appear immediately

See planting calendar for these climate zones

New Zealand - sub-tropical  

Home | Vegetables and herbs to plant | Climate zones | About GardenGrow | Contact us

This planting guide is a general reference intended for home gardeners. We recommend that you take into account your local conditions in making planting decisions. GardenGrow is not a farming or commercial advisory service. For specific advice, please contact your local plant suppliers, gardening groups, or agricultural department. The information on this site is presented in good faith, but we take no responsibility as to the accuracy of the information provided.

Site design and development by Hutchinson Software