Hello Charles In August I planted out some young carrot plants, which have since steadily grown. I have had a large water bottle over each group of 4 plants. What are their chances of over-wintering, should I now remove the bottles as some of the foliage is coming through the water hole (the 5ltr bottles are upside down) I live in Reading so nowadays the winters can be mild.
Hard to be sure Clair, I would look at harvesting soon as overwintered carrots tend to be holed by slugs, or to split as Leif suggests. I hope they have nice roots.
Also when the bottles are removed, carrot root fly may lay eggs around them. Autumn carrots are not straightforward: mine have mesh over against fly but a badger jumped on them which is not helping!