Growing Sweet Potato, also Kumara

Jan F M A M J J A S O N Dec

Not recommended for growing in USA - Zone 5a regions

  • Plant shoots or cuttings (Slips). Best planted at soil temperatures between 63°F and 95°F. (Show °C/cm)
  • Space plants: 16 - 24 inches apart
  • Harvest in 15-17 weeks.
  • Compatible with (can grow beside): Best in Separate bed
  • New shoots on Kumara
  • Well grown Kumara

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 will 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

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

Your comments and tips

27 Aug 21, Kirk McCoy (USA - Zone 10a climate)
If your sweet potatoes wont sprout it is because commercial growers spray them with a anti sprouting chemical. It can be removed buy giving your sweet potatoes a ascorbic acid bath for 15 minutes then rinsing. I use 2 tsp in a half gallon of water. you could also use crushed vitamin C pills.
25 Jun 21, Tina Lloyd (Australia - sub-tropical climate)
I want to try and grow nz Kumara / sweet potato I live in Ararat Victoria. And where can I buy slips please. Thanks
01 Jul 21, Anon (Australia - sub-tropical climate)
Plant a couple of sweet potatoes and use the slips from them. Use the new vine part. Strip most of the leaves off a 250-300mm piece. Did trench and lay flat with the growing tip out of the ground. Water a lot the first 2 weeks. That is the way commercial growers plant sweet potato in Qld
18 Jun 21, Khandi (USA - Zone 8a climate)
Can I plant my sweet potato slips in the ground now? I’m in Zones 7B & 8A. (SE Alabama)
29 Jun 21, (USA - Zone 8a climate)
It does say April to June.
04 Dec 20, Brian (New Zealand - sub-tropical climate)
My first attempt of growing Kumara was in heavy duty cardboard box, with a rigid base to stop the runner escaping. 1.5 kg tuber was harvested from one slip, I was impressed. Second year was in an old bath in full sun, 5 slips, harvest revealed a lot of small tubers. 3 kg. This year, 2020, I will combine my efforts in cardboard boxes again and the another bath. Layers of cardboard in the bottom of bath with mixture of compost, vermicast, gritty sand, soil and pea straw to preserve the slips from being removed by Wekas and or Pukekos. Liqiud fertilizer will be added to the new beds before planting, Intend to harvest before May 2012.
21 Nov 20, Len Lind (New Zealand - temperate climate)
I would like to try growing kumera here on Stewart Island in a tunnelhouse. Is there anywhere I can buy sprouts, slips?
18 Nov 20, Aitaua (New Zealand - sub-tropical climate)
Hi.. Can these sweet potatoes useful for planting here in Samoa?
19 Nov 20, (New Zealand - temperate climate)
They should be.
17 Nov 20, Henk Stengs (New Zealand - temperate climate)
I have experimented with kumara for several years in Greymouth with mixed success so last summer tried growing them in old car tyres. Their black colour absorbs heat thereby increasing soil temperature. Three sets of tyres were used, each stacked two high. These were placed inside our tunnel house on the surface in a sunny position and filled with soil, with one slip allowed to grow from each central position from late November. Harvesting took place in early April, producing a total yield of 9 kg, with about 60% of shop quality, my best result yet. When I harvested the tubers I saw that they were confined to centres of potential growth areas, with no root development at their circumferences inside the tyre rims. Therefore over half of the volume of soil in each pair of tyres was not utilised. This year I will plant 2 sllps per tyre pair, positioned diametrically opposite, with root ends inside the rims to see if this will give a better result. I am interested in hearing from anyone else who has tried growing kumara in tyres. .
Showing 1 - 10 of 261 comments

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I would like to try growing kumera here on Stewart Island in a tunnelhouse. Is there anywhere I can buy sprouts, slips?

- Len Lind

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