I started out 2013 with the ambition to grow as many root crops as possible… because it was the Year of the Root Crop! So, among my carrots and beets and turnips - and yacon, which did spectacularly well again this year - I ordered some oca seed tubers.
What's oca, you ask? It's another one of those great root crops native to the Andes (the most famous being the potato) that's high in nutritional value and apparently very tasty, though I've never had it. For more information, I will refer you to William Woys Weaver in this Mother Earth News article. Oca is day-length sensitive and only starts making tubers when the sun is up for fewer than twelve hours a day, which means it shouldn't be harvested until well into December. Not only that, but it's not frost-hardy, yet doesn't like the heat, so it must be planted after the last frost in spring but early enough that it gets established before summer, and preferably in some degree of shade (though not too much). And of course in the fall it may die of cold. So, yes, it's a challenge, but Weaver manages to grow it in Pennsylvania, so I thought I'd try it here in Maryland.
First mistake: that planting date business. As you recall, we had a very late frost in May this year, and because I was running around like a mad thing saving my tomatoes (or not) and then leaving on vacation, I left my oca tubers sitting in their little bag in my house (at least I hadn't planted them yet to get frozen out) and basically forgot about them until well after I returned home in early June. They finally went into the ground, or into potting soil in a container, about the third week of June, which is far too late.
However, the plants did well (I had the container in a partly shady spot on my deck) and finished out the summer growing out some nice spreading stems:
It's an oxalis, by the way, which those of you who have either grown ornamental versions or weeded out wood sorrel can tell.
Second mistake: getting busy and forgetting to fertilize, which oca really needs in the fall, according to Weaver. I did generally remember to water it, but that was all. The plants would probably have done better planted directly in the ground, too, but in a container they definitely need feeding.
When it started getting down near freezing outside, I covered the container with two sheets of clear plastic - which made watering tricky - and tried to keep the plants from succumbing. That worked until temperatures hit the low 20s this past week (and I was away all week) - that was it for the oca.
So I pulled out the plants and dug around looking for tubers; this is all I found:
The start of some edible tubers, but very few of them, and not big enough to bother with.
I am going to try again, and this is what I'll do differently:
- Put the seed tubers in at the right time.
- Grow in large containers, one plant per, and move them into the greenhouse that I am indeed getting someday, or:
- Grow directly in the garden and cover with a cold frame in the fall, and:
- Do whatever it takes to keep the plants alive until late December.
- Also, remember to fertilize and water.
Whether it'll be worth it in the end, I can't say, but growing oca is something I want to succeed at, at least once.