I just bought a Clementine Citrus tree

I would love any information on keeping it healthy and making fruit for yrs to come.

Thanks in advance for your help.

Sandy

Sandy, I've never grown a Clementine mandarin, but here's some information that may help you. As with all citrus, a mature tree is able to withstand slightly lower temperatures, but they will still suffer frost damage. Given the wacky weather we have had for the past few years, we have had multiple day freezes which can do more harm. Also as winter wears on, the soil cools off and no longer provides some of the heat you get when you cover plants. Many people cover plants using sheets. They really don't protect much especially later in winter.

If you are going to plant it in the garden, use a south facing wall to protect it. While you are in zone 9a, freezing weather can push down all the day to the gulf. Four Winds Nursery advises protecting Clementines below 32ºF.
http://aggie-horticulture.tamu.edu/extension/homefruit/citrus/citrus.html
http://aggie-horticulture.tamu.edu/citrus/mandarins.htm

From Florida, but still has some good information:
http://edis.ifas.ufl.edu/topic_citrus_home_citrus_culture


http://www.missouribotanicalgarden.org/gardens-gardening/your-garden/plant-finder/plant-details/kc/d389/citrus-reticulata-clementine.aspx

Information on cold hardiness:
http://www.fourwindsgrowers.com/our-citrus-trees/citrus-variety-info-chart.html
http://www.differencebetween.net/object/difference-between-tangerine-and-clementine/