By Glenn I. Teves, County Extension Agent, UH CTAHR CES
A cold, sweet, juicy mandarin is just the fruit for a hot day, and is high in Vitamin C. But what exactly is a mandarin? Mandarins are a group of closely related citrus, including tangerines, tangors, tangelos, and tantangelos. Tangelos are created by crossing a grapefruit or pomelo with a tangerine, while a tangor is a cross between a tangerine and an orange. A tantangelo is a tangerine crossed with a tangelo or between two tangelos. A mandarin crossed with a lemon is a lemandarin. After that, the rest are called citrus hybrids.
Many mandarin varieties grow well on Molokai, but only by growing them can you tell which one grows best in your area. Most mandarin varieties are seedy, but it’s dependent on what variety is pollinating them. Many mandarins do better with a pollinizer, including tangelos and some tangerines, so it’s best to grow more than one variety. Clementine and Orlando are considered good pollinizers, and bees help to spread the pollen around. Mandarins will also impart this seedy character to its relatives, even so-called seedless oranges, if planted nearby. Most mandarins are alternate bearers, bearing a heavy crop every other year.
Mandarins is believed to have originated in India, and there are at least three subgroups. The Ponkans are from India and are the most tropical in adaptability, but don’t like hot arid conditions. The Mediterranean or Italian, also known as Willowleaf, has a drooping habit. The King or King of Siam group is from Vietnam, and is among the largest fruits. The Satsumas or Unshu originate from Japan, and prefer cooler conditions. Tangerines are the most important group for breeding, and originate from North Africa, around Tangiers, Morocco where the name ‘tangerine’ comes from. An important tangerine is Clementine or Algerian, a small fruit with many good qualities and an excellent parent for Hawaii conditions.
University of Hawaii-recommended Mandarins for Hawaii include three groups, and selections are based on decades of field testing at UH Research Stations across the state, but not on Molokai. Recommended tangelos include Minneola and Orlando. Minneola (Duncan grapefruit X Dancy tangerine) has a characteristic nipple on the top of its fruit, and is great for making a bright red-orange juice. The fruit is large, very juicy, peelable, firm but tender, and does well on most rootstock. Sister to Minneola, Orlando is hard to peel. Recommended Tangors include Murcott or Honey and Ortanique and are crosses between tangerine and orange of unknown background.
Recommended tangerines include Fairchild, Fremont, Lee and Nova. Fairchild (Clementine X Orlando tangelo) grows best on Cleopatra rootstock. Fremont (Clementine X Ponkan) has medium to small fruit, with a rich flavor, tender and juicy, easy to peel, and early bearing. However, it’s susceptible to scab found in wetter areas, and also sunburn. At low elevations, it seems to bear a little several times a year. Both Lee and Nova are crosses between Clementine and Orlando tangelo and are technically tangelos.
Keeping plants healthy is one way to ward off diseases. Keeping fruits within reach, and harvesting with pruners prevents it from pulling off the stem and leaving a hole on the top. Pests include mealybugs and scales causing sooty mold. Controlling ants and using oils can control these pests. Citrus Swallowtails look like light-colored Monarch butterflies and will feed on leaves, and the caterpillar looks like bird droppings. Picking them off controls them. In rainy areas, scab can be a problem. Otherwise, tangerines are a super backyard fruit that can supply your daily Vitamin C needs.