Thursday, 3 March 2011

Overwintering Arracacha — Mustering the Survivors

Back in the Autumn I described (here) how I obtained Arracacha cuttings from Brazil, and was faced with the tricky problem of keeping them alive through a winter when they had just been plucked from Brazilian spring. Well, despite the particularly miserable winter, I think I am now in a position to confidently declare the survivors safe, seasonally syncronised, and ready for the growing season. Here they are...
Overwintered Arracacha, 2nd March
But it has been far from straightforward. The rooting and initial growing-on went easily enough. In fact, it seems that rooting can be successful even in relatively unfavourable conditions. Fellow gardener Ale Abrao, by way of illustration, placed cuttings outdoors in rubbly soil, with just an open-ended polythene cloche to keep off the worst of the winter.

Cuttings outdoors, 21st November
Four weeks after their October planting, they are growing away well despite some pretty grim weather conditions — near freezing, and grey cloud cover. These plants seemed reassuringly tough, and were doing almost as well as my mollycoddled indoor-grown specimens...
Rooted cutting, 7th December

But then the days got shorter, the light levels dropped, and the coldest winter for many years set in. Ale's 'outdoors' were finished off by -10°C temperatures. My plants stopped growing (apart from a few that bolted) and began to look yellow and sick. Here they are in mid January...
16th January

Many died, wilting back and rotting at the roots despite my efforts to give them light, warmth and dry feet.  By early February less than a third of the original plants remained.

But then a few cuttings which had apparently died, but not actually rotted, started to show signs of regrowth...
Apparently dead plant showing regrowth,  2nd March.
This one looked like a goner, but is reshooting from its central stem, and there is a tiny green bud, just visible, growing from the base.

Ale's plants, including his indoor ones, did not make it.
Back in October I also sent backup cuttings to Rhizowen and Frank van Keirsbilk. Reportedly they have both had the same difficulties as me; the latest news is that between them only one plant has hung on (well done Frank). Admittedly their cuttings were not as fresh as mine, having sat for a while, then suffering additionally in the post.

So, what next?  It's certainly still too early to plant out ( only 3°C  today), so they will staying in the greenhouse for a while yet.

The next target (apart from the obvious one of obtaining an edible crop) is to grow them through to autumn, then lift and store crowns to produce propagation material in late winter. The timings for this are all a big unknown, but are key to adapting this crop for growth in northern latitudes.

Given their noticeable tendency to flower in winter (I think induced by short day-length) I will also attempt to collect some seed for distribution this time next year.