Using organic fertilizer for your orange tree can help you feel better about your tree's health, environment and fruit. Organic fertilizer is readily available, cheaper than synthetic and allows for a more uniform distribution of the nutrients it provides. Whether you are a home gardener who wants to use organic means or a certified organic grower, your orange trees can benefit from organic fertilizer.
Fertilizer is anything that can be added to the soil to improve its nutrient content and support plant life. Organic fertilizers are those which come from living or once-living things. Examples of organic fertilizers are animal manures, compost, dried leaves, peat moss, pine needles, grass clippings, feathers and even cover crops grown solely for the purpose of turning under.
Soil testing can be done by your local extension office and can reveal specific soil nutrient deficiencies. They can also test the organic fertilizer you intend to use to determine if it will supply the nutrients your soil needs. They may be able to make a recommendation on specific organic fertilizers you can use and where to locate them locally. Without testing, it is difficult to know if the organic fertilizer you are using is supplying the needed nutrients.
Organic fertilizers break down more slowly than synthetic fertilizers. Synthetic fertilizers, which are typically water-soluble, break down almost immediately. Nutrients not immediately used by the orange tree tend to be washed away. They can enter the groundwater and become a pollutant. Because organic fertilizers break down more slowly, they supply a steadier stream of nutrients to the orange tree.
Many organic fertilizers are available at little or no cost because they are frequently readily available. Many gardeners now keep their own compost piles to use as fertilizer. Grass, leaves and pine needles are easily obtained at home or from neighbors. Many farmers are happy to find someone willing to cart off some manure from their livestock. Synthetic fertilizers are considerably more expensive because of the cost of manufacturing, balancing the nutrient composition, packaging and transporting the fertilizer.
Nitrogen tends to be the nutrient most needed by orange trees, as mature trees use about 1 to 1 1/2 lbs. per year. The timing of the applications are important. While some growers make several applications throughout the year, those made later in the year can be tricky. Nitrogen stimulates foliar growth. If this is applied in the fall or winter and a period of warm weather occurs, the tree may flush or produce tender new growth out of season. This can put the orange tree at risk of frost damage when temperatures return to cold. This situation is amplified with synthetic fertilizers, which release nitrogen quickly. Organic fertilizers reduce the risk of this condition because of their slow-release capacity. It is safe to apply organic fertilizers in the spring or fall.
Growing organically is a choice for many home gardeners and does not involve following the strict practices followed by certified organic growers. However, if you are a certified organic grower or wish to be one, consult with your local organic certification board before applying any organic fertilizer that doesn't come with organic certification.