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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11 May 17, Jody Waaka (New Zealand - temperate climate)
Kia ora.Im thinking of starting a kumara garden soon.Where do you buy the seed from
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13 May 17, Leslie Viljoen (New Zealand - temperate climate)
I'm not an expert but if you cut a Kumara into pieces, it will grow vines from the "eyes". We have one growing like crazy - but since it's cold now I think it's going to die.
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15 May 17, Daniel (Australia - temperate climate)
With Kumeras, they will grow if you plant a whole kumara but they wont produce tubers. The shoots that do grow from that can be used as cuttings, and as these new cuttings grow, you will get the Kumera tubers growing from those new plants. Needs a long warm summer to grow bigger tubers! Hope that helps
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23 May 17, Annie Davis (New Zealand - temperate climate)
I am also trying to find out if there is such a thing as kumara "seeds" and where they can be found?
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24 May 17, John (Australia - temperate climate)
Australian Seeds in Western Australia list a native sweet potato - Ipomoea costata but I don't know of any suppliers of seeds of the popular varieties. They are grown from cuttings as they establish quickly and will yield in their first season. Seedlings would probably take another year.
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28 May 17, toya (New Zealand - temperate climate)
If your lucky you can find some at local garden places for tipu which you can grow out of the kumara tubers by place half of it into water.. they should grow stems/vines which you can snap off & placing those into water to help roots grow... or just cut sections of the tuber off..... but when planting them... they need that late spring early summer heat. Then harvest around now or when frosty etc...... just my 5 cents here lol
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24 Jun 18, Richard Clough (New Zealand - temperate climate)
Annie...We simply bought a small kumara from a local supermarket, suspended it with toothpicks in a cut off coke bottle of water. When the shoots, or "slips" began to sprout (2-3wks) we then placed them in a small jam jar of water until roots began to develop, then planted out in fish bins of potting mix. We were late- late Dec & Jan, have just harvested. A lot were long & skinny, but perfect for the hot air cooker & crockpot. Some were like the shop sizes! We ended up with about 3-4 kg from a single 300g kumara (it's still growing sprouts on the laundry windowsill)! Hope this helps someone out there. Best wishes...
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25 Sep 17, Joss Roberts (New Zealand - temperate climate)
Is it possible for Kumara to be grown in Christchurch, New Zealand.
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26 Sep 17, Liz (New Zealand - temperate climate)
Kumara needs a long summer/autumn before frosts start. Your microclimate might suit it. It's probably worth a try. One kumara used to produce growing shoots would not be very expensive.
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19 Oct 17, Allan (New Zealand - cool/mountain climate)
Do you progressively mound up Kumara like growing potatoes?
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Showing 11 - 20 of 60 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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