Besides high vitamin C, oranges contain flavanoids under the sub-category flavanones. The flavanone herperidin, in animal studies, has shown it can lower blood pressure, cholesterol and inflammation. This flavanone and others are found mostly in the peel and pulp of the orange rather than the juice. Thus, you can be less meticulous about removing all the peel before eating. Vitamin C is vital in protecting cells in the immune system and disarming aqueous free radicals that cause cell damage (potentially carcinogenic DNA mutations). Compounds known as limonoids remain active for extended periods. Along with folate, potassium, fiber and many phytonutrients, citrus fruits are antioxidant, anti-allergenic, anti-carcinogenic and anti-inflammatory. They also help lower blood pressure, promote proper digestion and prevent kidney stones.
Vitamin and Mineral Content
Vitamins – C, Folate, B1 (Thiamin) and A
Minerals – Potassium and Calcium
Oranges help reduce the potential for a multitude of cancers: lung, colon, esophageal, mouth, pharynx, larynx and stomach. Antioxidants in vitamin C reduce effects of inflammatory conditions like asthma, osteoarthritis and rheumatoid arthritis. Phytonutrients, vitamins and minerals help reduce the risk of ulcers and atherosclerosis.
How to Grow
Oranges grow best in climates moderately warm year-round. Extended frost deforms or kills fruit. In cool climates, oranges must be grown in a greenhouse. Orange trees are bushy. Two types of oranges, sweet and sour. Sweet oranges are common for eating and comprise most of what is in the produce section of a grocery store. Best time for planting is spring or fall. They need as much sun as possible with as little wind as possible. This may require planting close to a fence corner, house corner or building a wind barrier. Soil should be slightly acidic; pH just above 6.0, and consist of a sandier loam with great drainage. Planting orange trees decreases soil drainage. If soil is denser, raise planting area by about 18 inches. Baby orange trees can be found at any nursery in a habitable climate. Before planting, amend the area with plenty of organic material. Plant the tree so the point at which branches converge is 4-5 inches off the ground. With multiple trees, space them about 25 feet apart to avoid nutrient competition or light deprivation. Throughout the first couple years, make sure roots get plenty of water. Be careful not to add too much chemical fertilizer, which can damage roots. Add a few fistfuls of planting mix heavy in fish bone, feather, kelp and other meals once in the spring and summer over the soil where roots are growing. During growth, if tree becomes too thick in certain areas, thin out by removing branches. Harvest when oranges have deep color. Twist off gently so as not to break off the fruit-bearing shoot. Fruits can hang ripened for up to six months. Immediately after harvesting, trim the same shoot (not branch) to roughly 5 inches to encourage more fruit-bearing shoots.
Popular outdoor pests include gall wasps. Indoor pests are aphids, scale insects and/or red spider mite. Gall wasps lay their eggs into new shoot growth in spring. Once hatched, larvae embed themselves in shoots, causing unnatural looking swellings (galls) to show up. The only way to control these creatures is to cut out galls when they appear and destroy them. Aphids prefer dry weather. They can be warded off via biological controls such as introducing ladybugs or by growing a plant like marigolds to attract them. Insecticidal soap controls a large infestation. Red spider mites, like aphids, thrive in drier temperatures. Attacks can be prevented by frequently spraying with water. If they attack heavily, a controlled spraying of rotenone gets rid of them.
Without fertilizer containing trace elements such as zinc, orange trees develop little leaf. This causes mottling of leaves and possibly deformed fruit. Avoid this by applying well-aged compost, manure or fertilizer with seaweed meal.