Tuesday, 20 July 2010

This Oca Relative Tastes Better than Oca!

Here's another Oxalis weed which has arrived on the plot.

I only took notice of it when I dug it out with a trowel during some detailed weeding. It had a substantial (for the size of the plant) tuber. Having a curious nature, I washed it and tasted a corner. It tasted good, so I munched the whole thing. It tasted sweet, moist, succulent, and had no hint of oxalic acid.
I've already mentioned Creeping Woodsorrel (Oxalis corniculata) which was easily identifiable by its bronze foliage, but I'm not absolutely sure what this one is. Checking a guide to wild flowers, I think the most likely candidate, given the dark pink flower and the cluster of bulbils, is Oxalis corymbosa, the Lilac Oxalis (but there seem to be several common names). A bit of research told me that it is another native of South America, now naturalised in the south of the UK.
The taste really is very good, but the tuber just needs to be a bit bigger to be worth harvesting. Given a bit of selection coupled with good cultural conditions,  this could perhaps be a useful easy-to-grow ground-cover crop for use in polycultures. It certainly seems to do well in quite deep shade, so it would work well with say, tall brassicas
I will look out for more, and give them a corner to themselves to see what happens. Perhaps if allowed to grow for more than one season the tuber will get bigger.

Update: My later post about this plant.

Some information on Oxalis corymbosa, and Oxalis corniculata here.
The Pfaf database also has an entry for this plant.

Wednesday, 14 July 2010

Oi! My Oca's Been at It!

Last year I never even considered crossing Oca and obtaining seed. After all, I knew it was impossible to get successful pollination without multiple varieties, and I was only growing one variety. I knew that flowering was infrequent, and had read that germination was erratic and difficult. All this was received wisdom a year ago.
But I've just found this little fella growing in last year's Oca bed, and as you can see it is not growing from a tuber that dodged the harvest - only roots are growing from the stem. It was close to the spot where a plant flowered last year, so I have to conclude that an Oca has 'done it' on its own.

So why did I carefully lift and check the roots of the plant, and not just terminate it with a hoe, assuming it to be an annoying volunteer in the wrong place? Well, a combination of three separate pieces of information coming together at the right time:
1. Rhizowen's comment elsewhere on this site ' ...mid stylar morphs are, so I've been led to believe, sometimes capable of self pollination.'
2. Rhizowen's post Another Oca Shocker, breaking news that Oca seed can overwinter and germinate outdoors.
3. My own comment on the same post "It would have been so easy to run them through with a hoe thinking they were volunteers..."
Then yesterday, just as in the comment, I found myself standing over a few defenceless Oca seedlings with a sharp hoe poised at their necks. Cogs whirred for a couple of seconds before I decided to check the plants below ground. All were obviously growing from tubers - apart from this one which was clearly not.

No-dig is the other factor that allowed this seed to make it. On a conventional plot it would have been turned 12" underground and would not have had reserves to reach the surface.

This can only have been from a flower that was self-pollinated - from the same plant, and possibly from the same flower, but given the chromosome-scrum that is Oca genetics, it may still produce some useful diversity. So in to a pot you go!