Growing Dwarf Citrus Trees Indoors, Part 1
If you want to grow your own lemons, grapefruit, tangerines, oranges, or limes but don't think you have the space or your climate is too cold, it is time to become acquainted with dwarf citrus trees.
Dwarf citrus trees have come along way in the past few years. Today's dwarfs produce tastier fruit (although some still feel it is not quite as good as their standard cousins), and dwarf trees produce fruit much quicker than other fruit trees — within one to three years on average.
There are two types of dwarf fruit trees, regular and genetic. Regular dwarfs are created by grafting a regular sized tree onto dwarfing rootstock. Genetic dwarfs are created by propagating trees to develop a very compact variety. You can identify a regular dwarf from genetic by looking for a diagonal scar located about 4 to 8 inches from the soil. This is the graft union where two different trees were grafted together, indicating it is a regular dwarf fruit tree. Genetic dwarfs also appear thicker and more compact, with closely spaced leaves and growth buds. Both types of dwarf trees produce normal-sized fruit.
Pot size is extremely important for dwarf citrus trees. While a 3-gallon container might be large enough for a seedling, a large container will soon be needed. A 10 to 15-gallon container allows the tree to grow to about 7 to 8 feet or more. A layer of stones or broken pottery should be placed at the bottom of the pot to allow for ample drainage. Use a light, airy potting soil mixed with perlite; then add just enough soil so that the root ball is barely covered. Make sure there is enough soil on the sides of the pot to allow the tree to absorb water.
Pruning should be done to remove any criss-crossing branches and suckers. Suckers are branches that are growing below the point where branching is desired. This is especially important on regular dwarfs for any suckers that grow below the graft union. Pruning can be done any time of the year on indoor citrus trees.
Older trees may require root pruning as well. This is done by removing the tree from its container and cutting off 1 to 2 inches of the outer rootball. Then, replant it with fresh soil.
Water, Food and Light
All citrus trees need bright, direct sunlight, and lots of water. Eight to ten hours of sun is required for good fruit production, less than than that and you may want to supplement with a grow light. They prefer areas that have a western or southern exposure. They like lots of humidity and will benefit from the use of a humidifier or by raising the humidity by placing them on tray filled with pebbles and water. Allow the soil to dry between waterings. Test the soil by sticking your finger about 2 to 3 inches down. If the soil is dry, it is time to water.
TIP: Our expert gardening advisor, Karen Thurber adds, "Citrus trees are especially sensitive to over watering. Be sure to check the soil before you water, water thoroughly, but do not leave you plant in standing water."
If the leaves begin to yellow, it indicates that your tree either has inadequate drainage, is being over watered, or both. Keep your citrus trees away from drafts and fertilize them at least once a month with a fertilizer that has a ratio of 2-1-1 and includes the micronutrients manganese, iron, and zinc.
TIP: Karen says, "Yellowing leaves on the NEW growth may indicate lack of fertilizer or an incorrect pH. Fertilize with a citrus fertilizer, being careful to follow the recommendations on the package."
Unless your house has a lot of bees in of it — and let's hope it doesn't — you may need to help pollinate your tree. This is done by brushing the stamens of any of the open blossom with a soft paintbrush. Do not rinse or tap your brush in between blossoms, as the idea is to transfer pollen from one flower to the next.
Finally, citrus trees can be prone to spider mites, mealy bugs, and scale. Spider mites can be treated using insecticidal soap, while mealy bugs and scales can be treated by rubbing the infected areas with a cotton swab that has been dipped in alcohol. This may require some persistence. Horticulture oil may also be useful for mealybugs and scale.
That's all there is to growing your own dwarf citrus tree indoors. Read on to learn more about various species of dwarf citrus trees.