Sunday 5 June 2011

The All-Tuber Polyculture Mound, Part 2 ... Room for One More

A previous post showed how last year I used mound culture to grow a mixed tuber crop (Yacon, Oca, and Chinese artichokes) with the minimum of labour input.

Here's what's left of the mound... 
...untouched since last December when it was torn open to yield over 20 lb of harvest.  As I anticipated, there are plenty of volunteer Oca and Chinese artichokes appearing amongst the annual weeds this year, so I only need to add a Yacon to restore last year's successful system.
Less than five minutes after the previous photo...
... and the weeds are blotted out by a heavy covering of garden compost, and a pot-started Yacon is added to the top of the heap.
This much compost might seem like an extravagance, until one thinks back to the amount of biomass which was removed at harvest; here's the near hernia-inducing Yacon root as a reminder...

I'm also adding a fourth member to the polyculture. The Hog Peanut, or Talet (Amphicarpaea bracteata) is not a true tuber-crop, so stretches the concept slightly,  but will clamber and twine amongst the Yacon, potentially fix nitrogen, and hopefully add to the overall interest and subterranean yield of the mound with its wacky underground beans.
It's another self-propagator by all reports, so like the Oca and Chinese artichokes, it should be back every year...

...whether I like it or not.

Update photo, 1st August...  ...five foot high an' risin'.


  1. Hellooo, just found your blog and I have a slightly random question about Oca... I'm growing it for the first time this year and have no real idea what I'm doing. I've planted out all bar one of my plants on the allotment but don't know if they need earthing up like potatos of if I just need to keep watering them and let them do their thing...

    I've also kept one plant back in a big tub in the greenhouse as a kind of test subject incase the ones on the allotment die... don't know if thats a good idea either but it seemed worth a try... :)

  2. Hi Paul and Melanie, earthing up will do no harm. It may even do some good, but you will also get a good crop by not earthing up - which is my preferred method, as it facilitates intercropping, making better use of space. I get good results planting between tomatoes or sweet corn.
    Far more important to the yield is to keep frost off the plants for as long as possible so that harvest can be as late as possible - December or even January. The one in a pot should be moved to a big pot, then moved outdoors (they do not like extreme heat), but moved back in when frost threatens. Good luck with the crop, let me know how you get on. Which variety do you have?

  3. Must try Yacon, if |I can find a tuber in Ireland.
    The sorrel you sent came up great BTW - wild leeks did not make it sadly.
    3rd tube has been added to Oca plants, coming along well

  4. Nice idea with the tuber mound. I am growing Oca, Yacon, and Taro out here in Southern California. All seem to do well, I am currently trying to track down different varieties of Oca.

  5. Hi Ian,
    just been doing some searching on Oca and found you and the incredible adventures of the polyculture mound. Any more updates since the last August picture?

    1. Hi Anonymous, I'm afraid that the harvest went unphotographed due to an impending house move, but as I remember it, the crop was similar to the previous year.

  6. HIgher,
    is anyone planting Oca with squash (spaghetti squash or courgettes)?