As the new year started I felt it was time to dig up the Yacon tubers. We still have not had another bout of hard frost and the weather continues damp and windy for the forseeable future. They will not grow any more in the ground however, and I’m wanting to tidy things up in the polytunnel and work out where things want to go next year.
I knew that the upper plants in the polytunnel seem to have done much better than those planted later, but I was still astounded by the difference this appears to have made. The early ones were planted on 26th March and the later ones on the 10th of June, having been in pots of compost until then. Both were treated the same once planted and had the same watering and feed (a bit of dilute urine occasionally).
The early ones grew much bigger above the ground, with the plants reaching higher than me – to 6 feet or so. The later ones lagged behind, with the ones in the tunnel reaching about 4 feet, and the ones outside less than one foot. The outside ones also suffered from wind burn and slug damage.
November was quite cold, with the frost starting to damage the foliage, especially of the outside plants. By the end of December even the plants in the tunnel were blackened, with the stems pretty dead, although the crown of the plants showed pink still with life.
To recap last year, I was pretty pleased with an average of about 8 ounces from 4 plants in the tunnel. Those had overwintered in the tunnel, but had no additional food, and the watering probably was less consistent. I also thought that they needed a bit more light, since the one closest to the overhanging mashua etc. was considerably smaller.
This year all the plants were harvested on 19th January. The ones outside had very poor tubers. Although the early summer was quite good, by the time I planted these out the best of the weather had gone, and the summer was typically cool for Skye. I think at least 4 plants disappeared completely, and another 8 had no tubers at all worth eating. Of the two plants I weighed, the tubers from one had two tubers at 3 ounces total, and the other one tuber at one ounce. To be fair, I did not expect these to do well, and I only planted them out because I did not know what else to do with the plants! I guess I need to be a bit more brutal and put excess plants in the compost. Let this be a lesson!
The late planted plants in the tunnel did pretty well with an average weight of just over 14 ounces – the best had 30 ounces so a bit better than last year. The real surprise was in the earlier planted plants. I couldn’t believe it when I dug the first plant – they actually looked like those you see on the internet and in books for Yacon tubers. Subsequent plants varied, but the average from these plants was over 96 ounces (2.74 kg). Some single tubers were over one pound in weight and almost the size of my forearm! The best plant had a yield of 159 ounces (4.5 kg).
I’m actually wondering what to do with this bounty! I think I may take some down to the shop for people to try. I’m also wondering whether they would dry well and make nice low calorie sweet snacks. I know you can make low calorie syrup, but I’m not sure whether to bother with that. So far I’ve just made a yacon and apple crumble which went down well. The tubers should store pretty well for a month or so – they may get a little sweeter with time, so there is no hurry to use them up straight away.