How to Make My Mandarins Grow Sweeter
In colder climates, plant your mandarin tree in a large container, using a good quality, slightly acidic potting soil. Move your container-grown tree indoors in fall. Your tree will grow larger in the ground than in a container. If you move it indoors for the winter, give it plenty of sunlight or artificial light. Reduce water in winter. A simple moisture meter can help you to determine the soil’s moisture. Special citrus fertilizers are available that include the correct N-P-K amounts as well as trace minerals this type of tree needs.
Protect your mandarin tree from frost.
You might call mandarin oranges tangerines, but whatever the name, this medium-sized citrus fruit is an easy-to-peel snack that’s loaded with vitamin C and good flavor. Many mandarin varieties exist: choose a young tree at your nursery for the best flavor, overall quality and speed of fruit production. Some of the available varieties of mandarins include the Gold Nugget, Tango, Kishu, Owari Satsuma, Dancy, Clementine, Murcott, California Honey, Kinnow, Kara and Page. The Murcott, California Honey, Kishu, Page and Kinnow produce the sweetest fruit.
Choose a sunny spot with good drainage to plant your mandarin tree if you live in a temperate climate zone that gets little frost. The planting area should receive reflected warmth -- from your driveway, a sidewalk, building or other source -- because heat will help it to produce sweeter fruit.
Dig in one part organic compost to every four parts of soil to increase the fertility of your soil; this will help to make sweeter fruit. When you set your tree into its planting hole, leave the top of the rootball, or crown, slightly above the top of the soil.
Water your tree when the soil becomes slightly dry down to about 2 inches deep. Thoroughly saturate the soil by running a hose at the base at a medium drip for at least 30 minutes. Be consistent with your watering and do not allow the soil to remain soggy.
Fertilize your mandarin tree with a high nitrogen formula plant food, such as one having an N-P-K ratio of 20-10-10. Repeat the fertilizer three or four times each year during the tree’s active growing season between spring and fall. Follow product label instructions for correct mixing and application.
Barbara Fahs lives on Hawaii island, where she has created Hi'iaka's Healing Herb Garden. Fahs wrote "Super Simple Guide to Creating Hawaiian Gardens" and has been a professional writer since 1984. She contributes to "Big Island Weekly," "Ke Ola" magazine and various websites. She earned her Bachelor of Arts at University of California, Santa Barbara and her Master of Arts from San Jose State University.