Harvesting oca and sieving the compost.

The oca has been cut back by the frost and was ready to be harvested. 

Oca plants Oxalis tuberosa  

I am storing them in an old paper bag that my red and white currants came in.  The bag was still quite serviceable and would keep the oca in fairly good nick for the winter. 

I am eating oca quite regularly now, including them in soups, curries and stews. 

Paper sac for the oca tubers.

They were just forked out and I didn't take much care to remove all the little tubers. If the little tubers grow next year, they will have to compete with the potatoes that are going to be planted here. 

Digging up the oca.

These tubers were red but you can get them orange and yellow.  The tubers were not very big and although some were about ten centimetres long, most were barely one.   You have to accept that the tubers are this size and be prepared to harvest them anyway.  The size does not affect their taste.


A thick layer of woody shreddings was put around the oca during the summer and, as you can see, it has all rotted away now except for a few bits here and there. 

The largest tubers

This oca plant had the most and the biggest tubers.  They are quite long - up to 10 centimetres and look a bit like pink fir apple potatoes.  However, most tubers are small and can be less than a centimetre in diameter.  Although the tubers are not anywhere near as big as potatoes, they are still an interesting and valuable addition to the dinner table.  The tubers can be scrubbed clean and cooked without peeling.  Slugs, snails and other tuber eating soil animals do not seem to bother at all with oca and the tubers are usually unblemished. 

The last plant harvested

They are quite easy to fork out and harvest.  The paper sac was about one third full when I had harvested all eight plants.  A handful of tubers will be kept to plant for next year's crop but the rest will be used in the kitchen. 

Taking out the oca left me with a strip of garden that was not covered with green manure. It would be quite difficult to get any green manure seed to germinate now even though it is unprecedentedly warm.  Furthermore, I have run out of green manure seed.

I also had a pile of oca tops that needed to be composted.  All the compost bins were chocker block and I could not fit anything else into them unless I started to empty them. 

So I was in a bit of quandary about what to do.  It was a compost turning day today and I thought that I would start to sieve out the compost while turning it.  I could see if there was enough well rotted compost to put along the strip of  ground that the oca had been harvested from.  It would cover the top soil and protect it from the rain while adding a little nutrient through leaching.  I could either spread it across the top of the new potato bed or dig it in during next spring.  The top soil here has not been composted or manured  because the oca were still growing; so I needed to add something to the soil particularly as this part of the allotment was not cleared of perennial weeds until the end of May.  Sieved well rotted compost seemed to be the answer. 

My trusty bread tray sieve.

The bread tray sieve was used to separate out the larger pieces of compost that could be returned to the bins.  The smaller well decomposed compost could fall through the holes and into the wheelbarrow.  During the time the compost is being turned, it reduces in volume and sinks down in the bins.  This means that fresh organic matter can be added to the top.  And that's what I did.  This causes a problem when it has to be sieved because there is compost at different stages of decomposition.  The bins should be filled at the beginning of the turning cycle and then no more organic matter added. 
Still, the bins produced some very good rough compost. 

Compost being sieved

Most of it passed through the one inch mesh of the bread tray.  What was left in the sieve was returned to the compost bin.  I got about four or five barrow loads of compost from just two of the compost bins and this was put onto the new potato bed. 
The compost was turned every two days for about one month. 

Some good rough compost.

Although I half filled the large green bin with the left overs, I had room to add the oca tops.  So the cycle continues.