Chicory is available in both the wild flower or herb variety and cultivated forms eaten as vegetables. The chicory family includes Witlloof chicory (sometimes known as French or Belgian Endive) which has blanched leaves, endive and the colourful radicchio or red chicory.
The white and yellow chicory available in supermarkets is of the Witloof or Sugar Loaf variety which has been forced to obtain this pale colour. Popular with guinea pigs but not as nutritionally valuable as its green and red cousins as the blanching process which prevents the leaves turning green also reduces the important and valuable nutrients in the plant.
Forced chicory found in the supermarkets has an inverse calcium to phosphorous ratio with 19-20mg calcium and 26-31mg phosphorous per 100gm. The vitamin C level is also lower than green vegetables at only 2.8-4mg vitamin C per 100gm.
The leafier green endive varieties of chicory on the other hand contain 52mg calcium and 28mg phosphorous per 100gm and provide 6.5mg vitamin C per 100gm.
You can also grow Witloof chicory and feed the outside leaves to the rabbits and guinea pigs which should have a better Ca:P, more in line with that of endive.