If you live beyond the sunny boundaries of the southern United States, you can still enjoy fresh, homegrown citrus if you plant small trees in containers. Wintered indoors in a sunny location, Meyer lemon, dwarf Baerr's lime, mandarin orange, tangelo and Kaffir lime trees will produce fruit while the snow flies. Their glossy, evergreen leaves and compact shapes make containerized, dwarf citrus trees decorative as well as productive.
Choose a container. Be sure the container has a drainage hole in the bottom. A wheeled base is helpful for moving your pots around---as the tree grows, the pot may become too heavy to lift. If you purchase a tree in a nursery container, choose a pot that is 2 to 4 inches wider. For barefoot plants, select a pot that allows the root system to spread out fully.
Prepare the potting soil. If you are using a standard commercial potting mix, add coarse sand or aquarium gravel to the mix to increase drainage. To 4 parts potting soil, add 1 part sand or gravel. Alternatively, use a commercial potting soil designed for cacti.
Select your trees. Grown outdoors, dwarf citrus trees reach a height of 10 to 12 feet. In a container, their size will be smaller---often half their normal height.
Give them enough sun and water. In summer, move the tree outdoors to a sunny location. In winter, keep the tree in a bright southern or western window. When moving the plant inside or out, make the transition gradually. Place the tree in light shade for two weeks to prevent leaf drop or browning.
Prune and fertilize as needed. Remove any suckers that sprout below the tree's graft scar (identified by a knobby growth on the trunk). Prune to maintain a pleasing shape and fertilize monthly with a timed release 12-12-12 fertilizer.
Bring trees indoors before the first frost. Know your local frost and freeze dates and use this information to protect your plants. Citrus trees can tolerate cold temperatures but will not survive a killing frost. If you are not able to bring the trees in before a light frost, cover the trees with a light fabric and wrap the bases in plastic or burlap.