welcome to GOY ,must say never heard of that before, do you have a photo ?

I doubt that your carrots have poppy flowers... I suspect that you have allowed annual poppies to grow and flower in your carrots! Weed them out now!

i agree with moon grower get rid of them now before they seed or they will be every where next yr

Poppies tend to grow in newly disturbed soil. I imagine that you may have grown veg in this spot for the first time this year?
As MG and Speedy say, get rid of them ASAP before they get the chance to re-seed all over your veg patch.

Thanks for the replies, we have dug them up. I wish I had taken a photo.

Lyn