We have 3 very large cucumbers that have not turned green? Are they likely to or if not what is wrong?
Christine, my cucumbers are green from the start. To my knowledge cucumbers don't turn green. Only ones that are a very pale green have been covered by leaves and not had enough light. Mine have now done and have been taken out of the greenhouse.
I'd pick one off and taste it.
I find that at this time of the year when it starts getting colder some of the outdoor cucumbers are more yellow than green.
A little net research gives four reasons for yellow or yellowing cucumbers.
1. They could be yellow-fleshed varieties such as the lemon cucumber
2. They have ripened past their green stage; we tend to eat our cukes before they are fully ripe and apparently they can taste bitter. Busy-Lizzie, I suspect this is why yours are yellow (or maybe in the cold they just stop producing chlorophyll which gives the green colour).
3. Over-watering which can rot the roots and stop the plant taking in oxygen
4. Some kind of virus, such as Cucumber Mosaic virus.
Christine, let us know if one of these reasons applies to your cukes.
It may well be why mine are yellow, had so many, couldn't pick them all. Had a very slow start as 5 of my six plants died, Telegraph - thought it was a greenhouse variety. The one that survived was planted outside to see what would happen. It was the most prolific cucumber I have ever grown! Then in June I just sowed Marketmore seeds wherever there were gaps in the veg garden and there have been lots of late cucumbers. But it has only been 3° at night several times recently.