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How to Fertilize Citrus Trees for Healthy Growth and Fruit

By: Angela Judd | May 8, 2025

Citrus trees are heavy feeders and need consistent care to thrive. Knowing how to fertilize citrus, including how much, how often, and when to fertilize, is key to keeping trees healthy and productive. Learn how to do it right, and you’ll enjoy strong growth, green leaves, and plenty of delicious fruit.

Branches of an orange tree with ripe oranges hanging among green leaves in bright natural light, a perfect scene for learning how to fertilize citrus for healthy, abundant fruit.

Why Citrus Trees Need Citrus Fertilizer

Citrus trees are unique. Their nutrient needs are different from most other fruit trees. They especially benefit from fertilizers formulated specifically for citrus, which contain the right blend of nitrogen, phosphorus, potassium, and essential micronutrients like magnesium, manganese, and iron.

Without these extras, you might see pale leaves, poor growth, or fewer (and lower-quality) fruit.

Look for a fertilizer labeled for citrus—these are balanced for what your tree needs most. I use this organic citrus fertilizer from Amazon and have had great results year after year.

A person holds a bag of Espoma Organic Citrus-tone Citrus & Avocado Food in front of green foliage, hinting at how to fertilize citrus for lush growth. The person’s shirt partially reads “ARIZONA GARDENERS ARE HOT.”.

When to Fertilize Citrus

In the low desert, it’s easy to remember when to feed your citrus trees: Valentine’s Day, Memorial Day, and Labor Day.

Person cleaning up dry leaves on the ground under a tree with a vacuum hose, surrounded by rocks and green foliage—an essential step before learning how to fertilize citrus trees.

This simple schedule helps break up the total yearly fertilizer amount into three feedings—just what citrus trees need to stay healthy and productive.

More specifically, here’s what the University of Arizona Extension recommends:

Oranges, mandarins, grapefruit:
Feed one-third in January–February, one-third in March–April, and one-third in May–June.
Lemons and limes:
Feed one-third in January–February, one-third in March–April, and one-third in August–September.

Lemons and limes usually need about 10% more fertilizer than other citrus. Grapefruit and pummelo trees often need half as much.

Need help choosing which type of citrus to plant? This article talks about 30 different varieties of citrus. Some oranges are best for juicing, and others are best eaten fresh. Still can’t decide? This article may help you decide which type of citrus tree to plant.

How Much Fertilizer to Apply

Your tree’s size determines how much fertilizer it needs. Here’s a general guide based on tree height:

Small (2–3 feet): ¼ to ½ pound nitrogen per year
Medium (4–8 feet): ¾ to 1 pound nitrogen per year
Large (10+ feet): 1¼ to 1½ pounds nitrogen per year

Divide the total amount into thirds and apply it according to the seasonal schedule above.

How to Apply Citrus Fertilizer

A hose releases water onto soil covered with dry leaves and mulch, helping prepare the ground for when to fertilize citrus and promote healthy growth.

When it’s time to fertilize, proper application makes a big difference. Follow these simple steps:

Pull back any excessive mulch from under the tree to expose the soil, keeping it off the trunk.
Sprinkle the fertilizer evenly around the drip line—that’s the outer edge of the tree’s canopy, where the feeder roots are most active.
Lightly rake the fertilizer into the top inch or two of soil to help it absorb and prevent runoff.
Water deeply to move the nutrients into the root zone.
Push the mulch back into place to help retain moisture and protect the soil.

Avoid piling fertilizer near the trunk or using too much at once—both can harm the tree.

For detailed guidelines on watering intervals, consult my monthly blog posts or the University of Arizona Extension Office’s publication, Irrigating Citrus Trees. Looking for more citrus-growing tips? Check out this article for additional insights on how to grow citrus.

Want more detailed recommendations on how to fertilize citrus by tree size and age? Check out the full Citrus Fertilizer Chart for exact amounts and timing.

Tips for Feeding Citrus

Use an organic citrus-specific fertilizer with added micronutrients.
Skip fertilizing trees in their first year or two as they establish. Instead, use only Nutrient+ and the worm casting, compost, and mulch method described in this blog post.
Over-fertilizing can damage roots and lower fruit quality—more isn’t always better.
Water thoroughly after feeding to help nutrients reach the roots.
Apply worm castings, compost, and mulch under the tree to build soil health and conserve moisture each season.

Three panels show: gloved hands holding compost, a wheelbarrow of shredded mulch with a scoop, and a pile of wood chips outdoors, illustrating types of garden mulch and how to fertilize citrus for healthy growth. — Worm castings, compost, and mulch

Support Tree Health with Nutrient+

In addition to fertilizing, I use Nutrient+ from Arizona Worm Farm during the growing season to help trees thrive and recover from stress. Nutrient+ isn’t a citrus fertilizer—it’s a powerful plant booster made from emulsified Black Soldier Fly larvae.

A person wearing green gloves pours liquid fertilizer from a white container onto mulch in a wooden garden planter with green plants and purple flowers, demonstrating how to fertilize citrus plants for healthy growth.

Nutrient+ supports tree health by promoting root development, enhancing soil biology, and improving plant resilience to stress like heat, frost, and sunburn.

Why I use it:

Helps trees bounce back from damage
Boosts microbial life in the soil
Improves nutrient uptake
Sustainable alternative to fish-based products

I apply Nutrient+ three times a year—Valentine’s Day, Memorial Day, and Labor Day—alongside fertilizer and mulch. For established citrus trees, use 1 cup undiluted for every 3 feet of tree height and water deeply.

You can apply it more often to stressed trees. Apply weekly until the bottle is empty.

Feeding Citrus Trees in Containers

Citrus grown in containers has different needs than in-ground trees. Because nutrients wash out of pots more quickly, container citrus should be fed more frequently but in smaller amounts.

A small citrus tree with ripe oranges grows in a barrel planter, surrounded by flowers and other raised garden beds. Knowing how much to fertilize citrus helps keep this vibrant outdoor garden thriving.

Instead of three large applications per year, break up the total fertilizer amount and apply monthly during the growing season, typically February through October in the low desert. However, it’s best to skip feeding during the hottest months, June and July, when trees are under heat stress and less able to take up nutrients.

Use an organic fertilizer formulated for citrus, and always follow label instructions for container-grown plants.

Tips for feeding citrus in containers:

Use an organic citrus fertilizer
Fertilize monthly during the growing season, except June and July
Water deeply after feeding to help nutrients reach the root zone

Container citrus also benefits from Nutrient+ applications to support root health and recovery, especially during periods of stress from heat or watering fluctuations.

For information about planting citrus in containers, see this guide to growing citrus in containers.

Feed Citrus the Right Way

Several ripe oranges hang from green leafy branches on a tree, with sunlight illuminating the fruit and foliage—a perfect scene to consider how often to feed citrus for healthy growth and vibrant harvests.

Healthy citrus trees don’t just happen—they need consistent, seasonal feeding with the right products and proper care.

Use a fertilizer designed for citrus, apply it on schedule, and support your tree with worm castings, compost, mulch, and recovery tools like Nutrient+ when needed.

The result? A vibrant, productive tree that rewards you with fresh, delicious citrus year after year.