Carrot Seeds Shin KurodaOverview Carrot requires a relatively long growing season than the other root crops. The optimum temperature is 7. 2 to 23. 9C for germination and 18. 3 to 23. 9C for growth. The best root colour develops at 15 20C. Temperature higher than 30C, particularly in later stages of development, induces undesirable strong flavour and coarseness in the roots Variety Details Smooth deep orange roots Slightly tapering roots Does well in subtropical areas High