Oca is a small tuber, not particularly prolific but with an exceptional taste. We really like it as an alternative to radish in winter, because it's harvest is perfectly timed, coming available in December and finishing (for us) around March.
I use a rating system to help me decide what to grow and it considers lots of factors, but the main ones are how tasty it is, howhealthy it is to eat, how expensive it is to buy, how big it's harvest is, when it's harvest period is and whether I can buy it organically and if not how much it's sprayed.
Oca score fairly poorly in this system because the yield is very low, compared to the time in the ground (May to December) but it has a few things to commend it. It is exceptionally crisp and crunchy and it has a sharp lemony taste (the leaves do too) because it's high in oxalic acid. It's at it's best over winter and it can't be bought in the shops. This late harvest period and unique, fresh crunch, however make oca the perfect replacement for radish in our salads and 80% of the people we feed love them.
<aside> 💡 However the oxalic acid that makes them so lemony, also means they should be eaten in moderation, I eat about 2 a day and they are only about 1 inch long.
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I find oca yields can be quite variable depending on the variety and the growing conditions, so estimating is hard. However oca is also generally a novelty plant, so I’d probably start off with just a few plants, that’s enough to see if you like it and to have enough tubers left over to plant more next year, if you do.
Oca grow well in containers and in the ground, but in my conditions containers are best. It grows fine in light shade, but also does well in full sun.
Save tubers from the previous year, I store mine in a frost free shed in egg boxes, I only need twelve of them, 1 tub for each of the 12 weeks of winter. In late March or early April I plant the tubers in moist compost in a 6 cell tray and I keep them moist, but not wet, frost free indoors. They soon sprout shoots and then I move them onto a frost free window sill, where they stay until late May., when they are planted in their containers.
In early autumn they are earthed up and then harvested once the foliage has died back after the first few frosts.
Unlike most crops that I grow that have several successions, oca has just one, plant in late May and Harvest 7 whole months later in December, with very little work in between.
I don't know which varieties I grow. I bought my original tubers as yellow and red and that's what I still grow.
<aside> 💡 I do however sometimes provide tubers for free to members of my channel, at buymeacoffee.com
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