They also provide an ornamental foliage display and fragrant spring blossoms. Citrus prefers subtropical, tropical or hot, dry climates. C. Some varieties are more cold tolerant, being able to be grown in Northern Florida, north of the commercial citrus growing belt. Use trifoliate as a rootstock to graft good varieties onto or sour orange rootstock if trifoliate not available. Use trifoliate, sour orange or Cleopatra for cold tolerance.
Kumquats are the most cold tolerate of all when dormant.
They only grow during the warmest weather and go dormant earlier than other citrus contributing to their cold tolerance. Once again use trifoliate for cold tolerance. Choose an elevated site if possible as cold air drains down hill. Planting on a slope offers some protection, but a normal house block prevents this. Plant on the south side of a house in the northern hemisphere and on the north side in the southern hemisphere for warmth.