20170302_085622 by
meganp08, on Flickr
Hello Svalli, several years ago I was given a no ID turban that I have been growing on from bulbils and it stubbornly continues to grow rounds for several seasons before it decides to finally divide. The larger rounds can exceed 5cm
Our winters are likely to be much milder than yours - we only get snow to ground level two or three times a year and am at 300m above sea level. The lack of vernalisation is definitely not a factor, although having said that last season was much milder than usual and there was a higher percentage of rounds harvested.