As the tree gets older, you can skip dormant season fertilizing and increase the amount of time between active growth fertilizing to once every two to three months. When nitrogen levels are adequate but phosphorous and potassium are low, select a 0-4-4 or 0-3-3 fertilizer. This publication provides Arizona gardeners and homeowners with practical instruction on how much commercial fertilizer to apply to their citrus tree, and when to make those applications. Orange trees are hardy in U.S. Department of Agriculture plant hardiness zones 9 to 11. The amount of fertilizer given should be adjusted, based on the results of the soil test. Ms. Raine is hoping to have her first novel published soon. It is fairly normal for young orange or grapefruit trees to have thick rinds here that protect the … Test the soil pH and nutrient levels to determine which fertilizer to use and if the tree can absorb nutrients efficiently. (30 to 45 kg) per hectare for P and 130 to 330 lbs. Do not over-fertilize, as this can make fruit less juicy, with thicker peels. Since no fertilizer is 100% nitrogen, use the chart to determine the amount of a specific type of fertilizer needed … Start by measuring the tree 12 inches from the ground and … The three numbers typically listed on the fertilizer bag represent nitrogen, phosphorous and potassium. When you think of oranges you probably think of lush green California or tropical Florida. Young trees don't need fertilizing until they've been in the ground for two years, according to University of Arizona Extension. Adapted from and replaces: Chott, G., Chard, C., Bradley, L., 1998. Fertilizing too much when the tree has a healthy appearance may actually cause it to produce inferior fruit. The phosphorus requirements of citrus trees are low, so a good citrus fertilizer will have a nitrogen- and potassium-heavy N-P-K ratio such as 13-7-13. Citrus trees (Citrus spp.) Required micronutrients may be present in the soil, but keep an eye on the tree for signs of micronutrient deficiency. Wait until after they recover from being transplanted and begin to grow. The best time to plant citrus trees in Arizona is in … Plan the perfect garden with our interactive tool →, University of California: Division of Agriculture and Natural Resources: UC Cooperative Extension: Citrus for the Home Garden in Contra Costa County, The University of Arizona Cooperative Extension: Watering Trees and Shrubs. ... Fertilizing. (60 to 150 kg) per hectare for K. Keep in mind that 1 ton = 1000 kg = 2.200 lbs. Keep a couple of important things in mind when fertilizing a citrus tree in Arizona in order to ensure maximum fruit yield and function. The mild winter temperatures are perfect for oranges… Start by the trunk and spread it about 4 feet out from the base of the tree on all sides evenly in a thick layer. Check the moisture saturation depth with a soil probe, which is a long, thin, metal rod. Soil pH and nutrient test kits are available at most garden centers. ** The three numbers typically listed on the fertilizer bag represent nitrogen, phosphorous and potassium. Water the fertilizer into the soil. Start by the trunk and spread it about 4 feet out from the base of the tree on all sides evenly in a thick layer. Sprinkle the fertilizer evenly on the soil around the orange trees beginning 6 inches to 2 feet away from their trunks, depending on the size of the tree, and extending out 2 to 3 feet beyond the drip lines, or outer edges of their canopies. Do not give orange trees fertilizer after the beginning of August. University of Florida IFAS Extension: Citrus spp. **Test the soil pH and nutrient levels to determine which fertilizer to use and if the tree can absorb nutrients efficiently. It is best to apply the sulfur or lime in the fall but it can be done at any time. (120 to 200 kg) per hectare for N, 67 to 100 lbs. They require nitrogen to set fruit, as well as other nutrients, which are often supplied with fertilizer. If the soil test indicates that nitrogen is low but phosphorous and potassium are at acceptable levels, use a fertilizer that supplies only nitrogen like ammonium sulfate fertilizer with a ratio of 21-0-0. In the spring months of late February and early March are recommended. 2. Nutrient levels change throughout the year as the orange trees use them and they are leached out of the soil with water. They like continuous warm weather. Orange trees should be given fertilizer three times during the growing season: once at the beginning of spring when the trees begin to develop flower buds, again toward the end of spring and at mid-summer. Test the soil for nutrient levels before selecting a fertilizer. ... Fertilizing Citrus Trees. Having an orange tree in your orchard is a wonderful addition. Soil in the top few inches often has a different pH from the soil deeper down closer to the orange tree roots. Cherry Tree Fertilizing: If your cherry tree has consistently grown more than eight inches, fertilizing is not required.