Thursday, 21 October 2010

Early Frost Carnage

Drat the BBC weather forecast!
4ºC was the forecasted minimum last night.  I believed them, but they got it wrong. The Oca bed looks pretty well devastated.
Yacon leaves are blackened...

...or at least the outermost ones. Those lower down seem to have survived damage, and I think the plants will recover.

This bed of Ulluco has been flattened too.

The only Andean to be unaffected is the Mashua, which is nonchalantly preparing to flower.

This is a freakily early frost for this area, and the situation is all the more annoying because I have rolls of mesh ready-and-waiting to give protection.

At first sight all seemed lost. But when I carefully lifted up some of the slaughtered Oca foliage, the optimist in me could see less-damaged stems underneath. I think they may live. Fingers crossed.
More checking revealed that the Oca in the 'all-tuber polyculture mound' have been protected, albeit sacrificially, by the yacon foliage. Free-range Oca on 'the other plot' are also alive and well, protected by their close polyculture competitor/companions.

This scare got me thinking. If it had been one degree colder, and all the Oca were killed this early in the year, they probably would not tuberise, and I'd be left with no seed tubers for next year. If the cold snap were to be geographically widespread, it might be very hard to find replacements. Does anyone keep Oca tubers dormant in cool-storage as an insurance policy against this sort of situation?

Not me, but maybe I should.


  1. I hate to say it, but this is the reason why we need ocas that tuberise during the long days of summer - hope may spring eternal, but disappointment isn't far behind. Tuber formation really needs to be comparable with day neutral potatoes - pretty much over by the time of even the earliest frosts. It's always upsetting and I spend an inordinate amount of time studying the weather at this time of year and praying for cloud cover or a change of wind direction. I fear for your ullucos, Ian. Perhaps an oca collection in vitro is what is needed. Not that hard to do, even by amateurs.

  2. I was thinking more along the lines of an egg-box full of tubers in the bottom of the fridge, just to the right of the beer. Perhaps with the added sophistication of a carrier bag as a vapour barrier.

  3. Interesting that your mashua was unaffected, I often find it to be more frost sensitive than the ocas.....

    Ulluco tubers can certainly be stored for over a year in the fridge - I've done that before.

  4. Cold air sinks, mashua rises (given half a chance).
    The oca grown up through a wire cage ('oca - be erect, not supine') are also completely untouched, and they are in the same bed as that in the top photo.
    Probably if the paths between my raised beds had been dug a bit deeper, the cold air would have drained off.

  5. My oca's been walloped as well, though it's not entirely dead. Maybe there's hope for it yet.

    I got a few flowers in September - only on one variety - but I suspect that may have been too late to produce seed.

  6. We had some frost as well, luckily I covered the oca patch, but some ot the higher leaves and flowers and seedbuds were hit. I don't know if I will still find a seed. We're expecting some nicer and warmer weather now. Were your mashuas more sheltered than the other things? Your yacon will recover, but don't expect that the roots will size up more, plants have to recover first. Maybe frost keeps out until Christmas??? I'm completely with Owen, we just need to break this daylength-sensitivity, and the ocas will become a very worthwile crop after that. When we take a look at all the oca varieties in the Andes, we'll see that they must be quite easily selected, we just need a bit of luck and determination to do so.

  7. Hi Robert. If they do survive, it may push them in to making tubers. I'm giving up on any ideas of getting seed this year now that all the flowers are frosted.
    Orrflo, good luck finding the seed heads. Mine were turned to mush by the frost, and in any case I don't think any were viable - I was unlucky with compatible flowering types. Still, I have learned from the experience.
    The Mashua were actually quite exposed, so I don't know for sure why they escaped. I have three plants in different places, and they are all okay.