It has been a good year for onions indeed. As part of an experiment I sowed the first batch mid November 2016 and they grew well. I sowed a second batch on New Years Day 2017. One of each of these I grew in the greenhouse.
The experiment did not go as I would have thought and the onions in the greenhouse went over weeks ago. The largest which was the November sowing only weighing 1lb 11oz.
The onions which I grew in a raised bed on top of a black membrane just kept growing. They had the same treatment as the onions in the greenhouse, including the same feed and at the same times. I did loose a couple of the outside onions, but on the whole they have done very well indeed, with the largest this year weighing in at a whopping 4lb 7oz! I also had a few onions just short of this mark.
I know from last year that these large onions do not store very well, so following a short drying-off in the greenhouse I will give as many away as I can.