Citrus trees are perennial fruit trees; they are groups of fruit trees that belongs to the family Rutaceae. Notable plants that belong to the citrus family are lime, lemons, grapefruit, orange, and pomelos. The citrus plant belongs to the genus of flowering fruit trees and shrubs.
The yield from a citrus plant is usually enhanced by several factors; fertilizer application is the most important factor influencing the yield (in terms of quantity and quality). Citrus tree requires nitrogen, phosphorus, and potassium in a higher proportion; of these macronutrients.
Nitrogen is the most important because it is required to aid the development of various tissues, and plant parts. Also, nitrogen is needed for flowering. The importance of nitrogen in citrus trees cannot be overlooked. At the end of this article, you will know the various sources of nitrogen, notable commercial nitrogen fertilizers for citrus trees, and the application and nitrogen requirement for citrus trees. Read up!
Sources of Nitrogen
The source of nitrogen fed to citrus plants determines the quality of the nitrogen and how the plants utilize it. The citrus plant is a perennial plant that requires long-lasting sources of nutrients; there are two main sources of nitrogen, namely:
#1. Organic Nitrogen
Nitrogen is available to gardeners through organic sources. Animal waste like chicken manure contains high amounts of nitrogen that is used by lemon trees after it is well composted. Legume plants, which fix nitrogen into the soil, are composted and mixed into the soil to add more nitrogen. Even though these sources enrich the soil, they do not contain enough nitrogen for hungry lemon trees when used alone.
#2. Inorganic Nitrogen
Most slow-release fertilizers contain ammonium sulfate. The numbers on the fertilizer package should be read, which tells you the ratio of nitrogen, phosphorus, and potassium in the mixture. A product with a ratio of 6-6-6 is recommended for use. To eliminate the guesswork in feeding lemon tree, a commercial fertilizer mix designed for citrus trees should be used.
A pound of fertilizer should be added each year until the tree is mature, around 8 years old. According to the University of Florida Extension, more than 20 pounds of fertilizer should not be used on a mature lemon tree.
Notable Commercial Nitrogen Fertilizers For Citrus Trees
#1. The Miracle-Gro Citrus, Mango, Avocado Shake ‘n Feed Plant Food
The Miracle-Gro Citrus, Mango, Avocado Shake ‘n Feed Plant Food comes in a 4.5-pound container. It offers continuously released plant food. This means you can shake out the recommended amount once, and it feeds the plant for a long time.
This fertilizer comes in an 8-2-10 (nitrogen-phosphate-potash) formulation. Most of the time, fertilizer formulas all include these three numbers, and they always indicate the percentage of those nutrients. It is common for citrus tree fertilizers to have more nitrogen and potash/potassium than phosphate because those nutrients get depleted faster.
This fertilizer can be used on existing and new in-ground citrus trees, as well as mango and avocado trees. It contains more magnesium, potassium, iron, and sulfur. Citrus plants need more of these minerals to prevent nutrient deficiency.
One application of this product can feed your plant up to three months. The continuous release option ensures that you do not burn nor overfeed your plant.
It also makes it easier to feed your plant. You measure out the right amount of food and sprinkle it around the tree. You don’t have to mix anything or guess at the right amount of fertilizer.
#2. The JR Peters Jack’s Classic Citrus Fertilizer
The JR Peters Jack’s Classic Citrus Fertilizer comes in a one-pound bucket with a resealable lid. It comes in the 20-10-20 formulation. It is designed to give the right combination of nutrients.
It works well on mangos, limes, kumquats, lemons, grapefruits, and oranges. It focuses on enhancing the micronutrient levels of your citrus fruits which helps you produce stronger branches, more fruit, and greener leaves.
The advanced formulation gives your plant high-quality nutrients. You can deliver more professional-looking results to your garden at home. Jack’s Citrus feed also helps your plants take in more nutrients. The plant can get nutrients through the leaves and roots.
With the product, you get a pre-measured scoop. Just use one scoop for each gallon of water when it is time to feed. Make sure you know how much water your tree needs to live and grow.
Citrus trees tend to require regular watering when they are new. This can take up to two years.
It is most helpful to dig a small moat around the tree, usually eight inches from the trunk, and keep it moist. When you fertilize, know how many gallons of water you’ll need and mix up that much food, and then feed your plant.
#3. The Jobe’s Organics Fruit/Citrus Fertilizer Spikes
The Jobe’s Organics Fruit/Citrus Fertilizer Spikes are more efficient than sprays because they don’t require any mixing. If you want to have organic fruits, it is important to use organic fertilizer and soil. However, this product is designed for potted citrus trees.
The spike version is quite easy to use. Each spike comes with all the nutrients your plant needs. You just insert the spike into the soil while following directions for placement.
The fertilizer is pre-measured for your citrus trees. Therefore, you feed each tree the right amount based on size. If your plant is 30 inches in diameter, you will need one full package of spikes to feed it.
All of Jobe’s Organics products come with Biozome. It is a combination of Archaea, Mycorrhizal fungi, and healthy bacteria. This proprietary blend improves the soil’s quality. It also increases root mass and helps your plants fight disease.
#4. Miracle-Gro 4852012
Miracle-Gro 4852012 makes it easy to feed your plants. The spikes are pre-measured with the fertilizer, so you plant it, and you are done.
You can get more fruit and lusher foliage than if you don’t feed your plants. This product does contain natural ingredients, but it isn’t considered organic.
It allows you to feed your citrus plants once each season (spring and fall). It is designed for citrus plants, but it can also be used on palm trees.
The easy-to-use spike system releases the nutrients right to the roots. Thereby getting stronger roots, larger fruits, and healthier plants.
#5. The Southern Ag Citrus Nutrition Spray
The Southern Ag Citrus Nutrition Spray comes in a 16-ounce bottle. It is designed to prevent the yellowing of the plant leaves. It can also correct yellowing disease if the plant has a yellowing deficiency.
It has five essential nutrients that are all balanced together. That way, your plant gets all the nutrients it needs to thrive. It contains magnesium, manganese, iron, sulfur, and zinc.
This product is suitable for all types of fruit trees, as well as ornamentals. It is designed to be sprayed on your plants.
A sprayer or use a watering can should be used for application, and the product must be diluted. Use about one tablespoon of product in a gallon of water. It is designed to work on all tropical fruits and citrus fruits.
This product allows you to spray the fertilizer onto the leaves and roots. It might be best to use it on the leaves if they have a deficiency. You can also spray it onto the roots to prevent mineral deficiencies.
Application And Nitrogen Requirement Of Citrus Plants
Before you decide on the feeding nitrogen to citrus trees, you need to determine the nitrogen requirement of the plant, after which you calculate the fertilizer proportions and apply. All these are what you need to learn and master.
Citrus Nitrogen Requirement
Young citrus trees need nitrogen to grow and develop. Each tree needs 2 to 4 ounces of actual nitrogen the first year, 1/4 to 1/2 pound the second year, and 1/2 to 3/4 pound the third year. Beginning with the fourth year, a mature tree needs 1 to 1 1/2 pounds of nitrogen per year.
How To Calculate Actual Nitrogen Required By Citrus Trees
Fertilizer numbers show the ratio by weight of nitrogen (N), phosphorus (P) and potassium (K), the most important plant nutrients. Nitrogen typically promotes growth while phosphorous and potassium promotes flowering and fruiting. But you need to know how much 15-15-15 fertilizer you will need to obtain 3 ounces of actual nitrogen. To do this, divide 3 by 0.15, the percentage of nitrogen.
The answer is 20 ounces or 1 1/4 pound. Ammonium sulfate (21-0-0) contains 21 percent nitrogen. To get 3 ounces of nitrogen Divide 3 by 0.21 and you get 14 ounces. Ammonium nitrate is 34-0-0. Urea is 46-0-0.
Application Of Nitrogenous Fertilizers To Citrus Trees
When using water-soluble fertilizer, mix it with clear water according to the package directions. Wet the leaves and soak the soil over the root zone. Granulated fertilizer is scattered under the tree over the root zone. Start sprinkling the fertilizer two inches from the trunk.
Finish the application when the scattered fertilizer covers an area twice the width of the lemon tree’s canopy. Do not pile the fertilizer on the trunk since it will burn the tree. Scratch the fertilizer into the top inch of soil and water the area to start the fertilizer working down toward the roots.