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 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

Your comments and tips

21 Mar 12, Malina Beatrice (USA - Zone 10a climate)
I found Kumara at Whole Foods in Encino, but they had them labeled "Japanese Sweet Potato." If I hadn't just seen them on a trip to NZ, I never would have known! Hope it helps.
02 Jan 12, Lisa Baird (USA - Zone 6a climate)
I also long for NZ Kumara, and have been unable to find them in the states. Where can I order tubers for growing or for eating? I'll start a greenhouse if needed. Thank you.
18 Nov 11, graham (USA - Zone 5a climate)
I would like to try to grow kumara potatoes in our green house as you say they need a long growing season. Can you advise me where I can buy tubers/seeds? Many thanks Graham
26 Jun 18, timothy (USA - Zone 5b climate)
I get my slips from Pioneer Garden and Seed in Villa Park IL. I grew sweet potatoes for two summers with great harvests. I am not sure why they say 5b is not good for sweet potatoes.
17 Mar 11, Kim Davies (USA - Zone 5a climate)
I ate kumara everyday when visiting NZ and loved it! Because it was less sweet than USA sweet potatoes. I am craving it and need to find out how and if I can get seeds and grow it in Virginia? Would love your help on this!
Showing 31 - 35 of 35 comments

Harvest once about HALF of the leaves start to fall over and die off (turn yellow) -- HOWEVER I'm not sure if you planted at the being of October or the end. Given good growing conditions it should take about 120 days -- if you planted at the end October then that is about 120 days.... but it could take longer -- and since the leaves have not fallen over, then I would say, it will take more time. If you planted at the beginning of October, then you are taking a lot of days -- and it could be that the growing conditions have not been optimal for the whole time.... and I would still wait for leaves to fall over... but I would start to wonder if perhaps for some reason all the conditions that your plant needs to have met in order to set tubers have not been met (nutrition, soil type/ph, water, sun light, temperatures etc.). Same rule for potatoes, harvest once the leaves started falling over and turning yellow. That is to say: as long as the leaves are a upright and green they are still collecting light and storing energy (making tubers - and making them larger)

- Celeste Archer

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