Tangerines are one of several types of mandarins. The name tangerine is not frequently used outside of North America. Portuguese mariners returning from Southeast Asia are credited with introducing mandarins through Tangiers, Morocco, hence they became known as Tangierines or tangerines.
The tangerine is a small yellowish orange sweet fruit. Natives of South and central America they are now grown outdoors in the southwest USA , and across the continent in indoor environments. They are a citrus and a relative of the mandarin orange. Many varieties of Tangerine can be grown indoors.
Tangerines prefer warm, humid climates, temperatures over 70 degrees F and full sun . The trees are somewhat cold hardy, but the fruit is easily damaged in any temperatures approaching freezing .
They keys to successfully grow Tangerines indoors are basically the same as with all citrus ,good light, adequate temperature and humidity , well-drained potting soil, proper nutrients, and consistent moisture. Without any single one of those failure looms.
Tangerine trees are generally container-grown, and purchased online or from a local nursery. They can also be propagated at home from cuttings, and seed. If you decide to grow Tangerine
Trees from seeds, allow the seeds to dry out for up to two weeks. Once dried, plant the seeds about an inch deep in good potting soil and cover with plastic wrap. Once the seed has germinated it should be placed in a sunny location.
Any container used for Tangerine trees and any indoor fruit trees, should provide ample drainage and room for growth. Any citrus started from seed will have a very long maturation period and a non dwarf tree will need to obtain substantial height before fruiting.
Tangerine trees can be put outdoors during the summer months, this is recommended to increase their chances of bearing abundantly. When grown indoors they do not have the advantage of pollinators, bees and other insects. Placing them outdoors during the summer allows for this. You can also hand pollinate them See : Indoor Pollination
Prune as necessary to shape the tree. Pruning will also encourage new branch development, and create a more compact and appealing shape. Tangerine trees that don't get enough light can become spindly and unhealthy. Should this occur, prune about 1/3 off the top growth and place the tree in a sunnier location or under grow lights.
Tangerines require 8-12 hours of sunlight daily to prosper, 5-6 hours to just survive . Grown indoors, a South or west facing window is best.
Not that I'm comparing apples to Oranges, or Tangerines as the case may be, but citrus plants unlike other fruits do not normally go through a period of dormancy or hibernation in the winter, they will however tolerate slightly lower light conditions during their phase of slower growth.
Supplemental light , such as grow-lights or fluorescent plant lights will help them produce better, especially if your location is not optimally sunned.
Night time temperatures no lower than 55°F and daytime temperatures around 70 - 80°F are ideal. They will usually tolerate temperatures hovering above 32 degrees for a few hours or heat over 100 degrees so long as they are well watered. Temperatures should however , not be a major problem in an indoor environment. Temperatures below 55 will will invoke a dormancy , extended periods below 55 could result in their premature demise.
You should be using a light [low clay], well draining soil mixture with an abundance of peat, and perlite or vermiculite. Adding addition perlite or vermiculite to any soil you purchase is advisable. You can also add wood chips, redwood shavings or even hamster bedding and semi-sterile compost [Not from your back yard compost heap] in moderation . Using dirt from your yard is a bad idea.
I prefer to fertilize my tangerines by a slightly differing schedule from other citrus in my collection. Fertilize annually starting in the early spring when new growth has begun to appear and repeat this process and in Mid spring and again in late summer .
One-year-old tangerine trees should be fertilized with an additional cup of either ammonium sulfate or citrus tree fertilizer divided equally over the three feeding sessions. Increase the application to 2 cups for 2-year-old trees and continue this regimen for the third year. By the 4th year cut back to 1 cup twice annually - starting with the early spring and ending in late summer. It's okay to add some other fertilizer from time to time but don't get carried away. Excessive fertilizer can do more harm than good. Fertilizer developed specifically for citrus trees is naturally a good choice.
Water regularly to keep the soil moist, not saturated, just moist. A layer of decorative sterile mulch such as bark or any other organic mulch is advisable to retain soil moisture. Allow the potting soil to slightly dry between watering, not "DRY-OUT" just slightly dry.
I prefer to water modestly 2 - 3 times weekly , test the soil by hand - stick your finger in about a half inch to be certain it is semi dry before adding more water. Over watering is just as deadly as under watering.
In winter months, artificial heat dries the air so plants will need added humidity. Misting the Tangerine trees foliage with a simple spray bottle is good way to help citrus cope with the indoor environment in winter. You can also add moisture with a humidifier, or by placing them, containers and all on a pebble filled tray with water added to the top of the pebbles.
Tangerine trees are susceptible to spider mites, mealy bugs and scale. Check the trunk for mealy bugs and scales. Wipe the foliage periodically with a damp paper towel or sponge. Dust will attracts pests, they hide themselves and their egg clusters in the dust while parasitizing the plant . To treat spider mites, spray your plant with insecticidal soap or horticulturist oil, which will smother the insects. clean the foliage, top and bottom sides of the leaves as well. Neem Oil is effective against Scales and Mealy bugs. Rubbing alcohol applied with a Q-tip will also work in mild infestations.