Carrots used to be... purple???

Orange carrots were an invention of the Dutch in the 1500s... for the House of Orange...

http://www.carrotmuseum.co.uk/history.html

You can buy purple carrot seeds from Park Seed

http://www.parkseed.com/webapp/wcs/stores/servlet/StoreCatalogDisplay?storeId=10101&catalogId=10101&langId=-1&mainPage=prod2working&ItemId=5074&PrevMainPage=textsearchresults&scChannel=Text%20Search&SearchText=carrots&OfferCode=TH1