Growing Sweet Potato, also Kumara

Ipomoea batatas : Convolvulaceae / the morning glory family

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

Not recommended for growing in New Zealand - cool/mountain 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

Your comments and tips

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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.
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19 Jun 22, Maria (USA - Zone 10a climate)
Thanks for the tip! I am trying for the first time and will do this :)
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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
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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
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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)
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29 Jun 21, (USA - Zone 8a climate)
It does say April to June.
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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.
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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?
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18 Nov 20, Aitaua (New Zealand - sub-tropical climate)
Hi.. Can these sweet potatoes useful for planting here in Samoa?
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19 Nov 20, (New Zealand - temperate climate)
They should be.
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Showing 51 - 60 of 316 comments
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Plant the tubers that you want to grow but in a separate bed. They will sprout lots of shoots which will also have roots near the base. When the shoots are 40 to 50 cm long put a fork under the tuber and gently lift it out. Separate the shoots and plant them in the bed you have prepared for them as indicated in the article above. Last year, before I knew this, I planted several tubers where I wanted them to grow but after learning the right method I dug up three and planted out about 50 slips. The slips can be left in water while you are waiting to plant them out and in a few days mine put out prolific roots where the base was under water. You can also start the sprouting inside, cutting the tops off tubers and putting the cut down in shallow water, then planting them out when they start to sprout. Roots will also start growing but later than the shoots. Look for the eyes in the tubers as they are where the shoots come from.

- Paul

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