Thursday, 28 October 2010

Brazilian Arracacha Arrives

Arracacha (Arracacia xanthorrhiza)... may require some introduction. It's a high-yielding starchy root-crop popular in southern Brazil, and parts of the Andes. A member of the Umbelliferae family, and sometimes called the Peruvian Parsnip, it forms sizable crowns with several good-sized edible roots growing below, and propogation shoots above.
All sounds good so far, but it's another crop that has failed to make an impact outside its home territory, probably because of the tricky combination of frost tenderness, and a required growing season of up to 14 months.
Reports are divided on whether it is day-length sensitive.

So... these are arracacha propagules - unrooted buds cut from the plant's crown. This is a named variety, 'Governador Amaral', recently developed in Brazil to have a short growing season — short enough perhaps to crop in a temperate climate such as the UK.

Just like the black Oca which I received recently, these cuttings are seasonally desyncronised, having just been whisked from Brazilian spring to English autumn. I have gleaned enough information to know that they would probably just rot if I tried to induce dormancy using low temperatures, so I'm going to have to try to get them rooted, then nurse them through the coming winter.
Here they are installed in a cozy propagator.
There are bound to be some casualties but if most of them root, I'll have some little plug plants to spare for my friends.

UPDATE 9/11/10
After a couple of weeks, almost all of them have burst into vigorous life, above ground at least. Checking the cut surface of a couple reveals a few short roots starting to reach down into the compost.

They have been spending the nights (and colder days) indoors, in the propagator under a window, but whenever the sun shines and the greenhouse warms up a bit, I'm moving them out to catch what daylight is available. I've even washed the greenhouse glass especially for them!

UPDATE 22/11/10
Almost all have rooted well, and made nice little plug plants. I used a very sandy open compost to minimise the risk of rot, and the roots have raced down through it.

Had I used a normal plug tray with such a crumbly compost, it would have been almost impossible to remove the plugs intact, but the process was, as always, trouble-free using a self-ejecting Agralan plug tray.

I'm potting on promptly to avoid a congested root ball, just in case it results in humorously distorted comedy vegetables at harvest time. Peruvian folk-lore would apparently suggest that this can be a problem; the recommended precaution for growers there is to avoid sleeping with crossed legs during the planting season.

Mission accomplished with regard to rooting. Now I need to slow them down till spring comes, so I'll leave them in an unheated greenhouse from now on, only bringing them indoors on really cold nights.

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.

Saturday, 16 October 2010

What's that Other Andean Tuber...

...a bit like Oca, only dull brown, mundane, and suffers from lots of diseases. What's it called ... oh yeah -  the potato.

Straight away, I had better apologise to spud fans for that admittedly gross generalisation, and I do have to acknowledge a certain appreciation for Solanum tuberosum ordinaire when it arrives on my plate, even when it is dull brown, and agrochemical dependant.
But if we look beyond the few varieties grown en-mass for the supermarkets, it is actually a hugely interesting, diverse, and delicious food plant. For example...
Harvested 7th October
...these are the last of my spuds to be lifted - the late maincrop black-skinned and purple-fleshed Négresse. I've maintained this variety for a few years now, but there's very little information available about it. Some sources say it is the same as Vitelotte, and was brought from Peru to France in 1815. Cats tripe has photos of Vitelotte here and I'm not convinced they are the same. Vitelotte is said to flower rarely, which is not my experience with Negresse. Vitelotte shows white marbling through the purple flesh in all photos I have seen, whereas my Negresse is purple throughout, thus:

A US potato list gives it a mention here and surprisingly suggests that it is not Solanum tuberosum, but Solanum ajanhuiri.
So in summary, it's exotic, mysterious, beautiful and day-length sensitive (another way of saying 'late maincrop'!), all of which would be a fair description of Oca.

Thanks to Paul Coleman, potato breeder, for letting me try the next three varieties. All have something in common; they are crosses between Solanum tuberosum, and Solanum phureja.
The first, Mayan Gold (left below)...
... is commercially available and well enough known as a gourmet potato.
The second, nicknamed "Mr Nutty"  (centre) is more interesting, and cannot hide its tuberosum parent, Pink Fir Apple. It tastes fantastic! Here's another shot showing its graduated skin colour and primative good looks.

And finally a bright yellow-fleshed main crop which makes great buttery mash.
I've had universal unprompted positive feedback on the taste of all three varieties, so I'll be saving for next season.

Mayan Gold, harvested 22nd August.
And what's this all got to do with Oca? Not too much, except it's worth asking why the potato is a world nutritional mainstay, while Oca is almost unknown, when both started out alongside each other, with similar characteristics and limitations. Why did the potato benefit from selection and breeding in Europe, while Oca plodded along in Andean fields and terraces? It seems unlikely that the Conquistadors only picked up the plain-looking potatoes from markets when they were right next to spectacularly colourful Oca tubers. Maybe the tubers that looked best, and needed no cooking got scoffed by the ship's crew on the way home to Spain, leaving only the potatoes. That's my theory.

Anyway, Oca has some catching up to do.