The calamondin orange tree, also known by its Latin name Citrus mitis, is one of the most popular citrus trees suited for container culture. The tree tolerates lower temperatures than most other citrus, but is still susceptible to cold damage. For this reason, American gardeners grow calamondin in containers for easy transport indoors when temperatures drop too low. Prized for its edible fruit, fragrant flowers and attractive form, the calamondin orange tree makes a great addition to a patio or indoor garden. The most important part of caring for the tree is providing the correct temperatures for optimal growth.
Place calamondin orange tree in a location that receives bright sunlight during summer and partial shade during winter. For the best results, keep the plant outdoors for as long as possible in the spring and summer, and bring indoors only when temperatures drop.
Keep the tree at a constant temperature of 70 to 90 degrees Fahrenheit throughout the year, whether indoors or outdoors. Although the tree will tolerate colder temperatures, it may not produce fruit when exposed to cold for long periods.
Water when the top 1 inch of soil is completely dry, about once every five to seven days. Drain away excess moisture after watering to reduce the risk of disease. Reduce watering frequency to once every 10 days during winter, when the plant grows less actively.
Feed Calamondin orange tree once per month during spring, summer and fall using a water-soluble fertilizer. Apply a slow-release fertilizer to the soil during spring to add additional nutrients. Reduce fertilizing frequency to once every five weeks at one-half the recommended dosage during winter.
Use a damp sponge to wash the tree's foliage once every three to four days to prevent pest infestations and to keep the leaves dust-free and attractive. Clean the leaves gently with lukewarm water to prevent damage or shock.
Harvest calamondin orange fruit when it is firm and yellow to yellow-orange in color. Use soon after harvesting, as the fruit has thin skin that dramatically reduces its shelf life. Store for up to one week in the refrigerator.
Transfer the tree indoors during late summer or early fall, just before temperatures drop below the recommended range, and keep in a room with partial shade throughout winter. Move the plant back outdoors during spring, as soon as temperatures warm to an average of 70 degrees Fahrenheit.