They do need a longer exposure to sunlight, at least in northern conditions. Sun is very low in winter, and uncomparable to the high sun intensity they have in the tropical regions. I've experimented a bit with them, and they need at least a month of exposure to sweeten them up, but after that time you can eat them out of hand, just raw, without a trace of the oxalic acid. Some varieties should sweeten up more than others, but I tried different ones and the result are the same every time. I like them very much when they're first cooked, after that baked, and add a bit of salt pepper and cumin to them, that's just excellent, even when they're still unsweetened.
Here's the photo I promised...this is the yield off one plant. Sorry no scale but you can probably guess accurately from the texture of the sidewalk underneath. Each of the larger tubers is roughly the size of a typical radish. Smaller tubers roughly the size of a pea.
Peace Seedlings grew several hundred pounds of oca and about a 80 pounds of mashua last year. Write for a free seed list to 2385 SE Thompson St. Corvallis OR 97333 or online at PSeedlings.com. The predominant oca cultivars are Amarillo, Grande, Hopin, Rebo and Mexican Red. The mashua is Tropaeolum tuberosum v. filifera from Colombia (north of the equator). It is exceptionally more productive than Ken Aslet and other probably Bolivian cultivars (south of the equator). The tubers and creamy white with a mild anise fragrance/taste.
For those of you who want to grow oca but have early frosts, grow them in pots! I was running late with my planting dates last year and the bed I was preparing for the ocas wasn't ready so I had to plant them somewhere. As I had six larger pots with tomatoes in them, I put a couple tubers in each one of those. And although they were planted with tomatoes (which I cut after I picked all the fruits from them) they manged to give me some tubers, not many but enough to plant them this year...
If they had been planted et the right time and by them selves they would have given me a decent crop as I was able to remove the pots inside when there was danger of frost...
I don't know why that is happening, RobertB, but I can tell you that mine sometimes flower twice a year, once in summer, once in autumn. A problem that I have had is that sometimes summer blossoms abort. TTYTT, I suspect they are badly virus-infected. If I can ever get seed I'll raise a batch from seed to thwart the viruses.
Thanks, Cortona, I had suspected something like that since it's an Oxalis and that is true of most Oxalis. They've got some sort of thing going on like the "pin" and "thrum" flowers of Primroses, except more complicated than that--I think they have 3 different types of flowers, and not being a botanist, I never quite understood it. I have a few unrelated strains, hopefully two that are compatible find each other some year when I get a good crop of flowers. This was a bad year for it because of the La Niña.
It's too late for a lot of Andean crops that have gone sterile from virus buildup. It would be a shame if that happened with Oca.
Wish me luck on my Oxalis obtusa; I have 3 cultivars of that one. Not for eating (the corms are smaller than a pea!) but just for fun. That's the one from South Africa with absurdly large and gaudy flowers compared to the size of the plant that produces them. I intentionally got some pink shades and yellow shades to see if I could get a rainbow of intermediate colors this species is famous for.
Post by wildseed57 on Oct 25, 2011 10:38:12 GMT -5
`I didn'y grow any Oca, this year the last time I gre any was about three years ago aand i wasn't able to watch them and the summer heat just burnt them up. I'll have to check with peace seeds and try and grow some of theirs also I think Horizon seeds has them also so i may try getting some of what they have the problem is we get our first frost in late October then it wams back up for a couple of weeks, so I could lay down a cloth to keep them safe from frost. I wonder though if that will give them enough time to produce some tubers least wise enough to save over for the following year? The Idea of growing them in pots is a good Idea as I could move them onto the back porch which is covered or put them in the storage shed. George