How to fertilize citrus trees
Orange trees have certain needs in nitrogen, phosphorus, potassium and calcium. Some microelements are also necessary (iron, boron, magnesium, aluminum, manganese, zinc and copper). Lack of nitrogen slowly decreases vegetation and causes yellowing of the foliage of the tree, premature defoliation and decreased production. However, the needs differ significantly, depending on the age of the tree, the variety, and the fruit’s intended use (juice production or table oranges).
We can say that the annual fertilizer requirements of the orange tree are 260 to 440 lbs. (120 to 200 kg) per hectare for N, 67 to 100 lbs. (30 to 45 kg) per hectare for P and 130 to 330 lbs. (60 to 150 kg) per hectare for K. Keep in mind that 1 ton = 1000 kg = 2.200 lbs. and 1 hectare = 2,47 acres = 10.000 square meters.
Under normal conditions, the supply of 260 to 440 lbs. (120-200 kg) nitrogen per hectare can be beneficial (ask a licensed agronomist in your area). Orange farmers often provide 5,5 – 7,7 lbs (2,5-3,5 kg) P2O5 in every adult tree for 4-5 consecutive years. In many cases, they may also add 3,3-6,6 lbs. (1,5-3 kg) K2O in every adult tree for two consecutive years. The best time to apply fertilization is during spring. However, these are just common patterns that should not be followed without making your own research.
Another pattern for adult trees intended for table oranges includes 3 main fertilization applications per year. Farmers start the applications at the end of winter (February), when they apply for each tree 4.4 to 6.6 lbs. (2-3 kg) of a top dressing similar to N-P-K 12-12-17. The second application takes place during the fruit setting stage (late spring May-june). At this point, they apply for each tree 2.2 to 4.4 lbs. (1-2 kg) of fertilizer, providing only N and K to the plants. Heavy nitrogen fertilization shall normally be avoided at this stage, because it will probably cause blastomania and will inhibit the fruit setting of the trees. The final application is performed during the fast growing stage of the fruits (normally late summer, July-August). At this point, producers apply for each tree 2.2 to 4.4 lbs. (1-2 kg) fertilizer. Fertilization during fruit growing stage aims at increasing the fruit’s size and weight.
Application is generally performed by soil or foliar fertilization. Foliar fertilization is a fast an effective method when iron, magnesium, boron and copper deficiencies have to be addressed during critical stages of crop development. The soil pH must also be checked at least once a year. If soil pH is greater than 7, then you may have to take actions in order to correct it through applying an acidifying fertilizer, after consulting a licensed agronomist.
However, these are just some common practices and should not be followed without making your own research. Every field is different and has different needs. It is beneficial to test your soil at least once a year, and take corrective actions after consulting an expert.
You can enrich this article by leaving a comment or photo of your orange tree fertilization methods.
10.) Orange Tree Fertilizer Requirements
Do you have experience in Orange Tree cultivation? Please share your experience, methods and practices in the comments below. All the content you add will be soon reviewed by our agronomists. Once approved, it will be added to Wikifarmer.com and it will influence positively thousands of new and experienced farmers across the world.