[NASH]

Variety is New Red Intermediate and i am growing them in 12" deep multi purpose compost in 2" wide trenches lined with black plastic which has also kept the weeds out wonderfully well but several have now turned purple, when peeled for cooking they are normal Orange colour underneath.

[aelf]

is it sunburn? mine are purple on the exposed tops. must get some factor 40 

[NASH]

Mine have gone purple all the way to the bottom of the root.

[tam]

You can get purple carrots and they are often orange in the centre:



(excuse my weedy orange ones)

But, I don't know if that particular variety is meant to be.

[FCG]

Nash perhaps your carrots were mis-sold? Purple carrots where the norm until William of Orange brought them over. Perhaps they are showing some old genes in the colour department?