Fertilizing Citrus Trees: Learn When To Fertilize A Citrus Tree

Citrus trees are beautiful fruit-bearing trees, but they sometimes require a little extra nourishment with citrus fertilizer.

Taking care to fertilize your citrus trees at least twice a year will pay off and provide healthier fruits for harvesting.

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Bag of Citrus Plant Food Fertilizer | PlantCareToday.com

When To Fertilize Citrus Trees

When citrus trees bloom depends on the variety and species, but having the information will put you in place to take the first step in fertilization. Understanding your area’s climate and season cycle is key to knowing when and how your citrus trees will bloom.

You should first apply fertilizer right before blooming time. As the air starts to warm following winter, citrus starts to “wake up” and prepares to produce seeds and, by proxy, blooms. 


You want to get fertilizer down before the bloom occurs, but not while the tree is still totally dormant from winter. A good rule of thumb is to plan on Valentine’s Day for the first fertilization on mature citrus trees.

In a few months, you can apply a second helping of citrus fertilizer. This application should occur around late spring (May), in the general ballpark of Memorial Day.

Finally, if your citrus trees need it, you can apply a third and final round of fertilizer. This last round can occur about a month after the second one. Avoid fertilizing too late in the season, as it can cause your fruit’s quality to decrease.

It’s quite common for gardeners not to fertilize their citrus trees regularly enough, or they don’t do it at all. Citrus trees often require extra fertilization and this is normal for them. It is not a reflection of your gardening skills.

Despite citrus trees needing fertilization often, it’s better to err on the side of under-fertilization as opposed to over-fertilization. Remember, you can always add more but not take any away. Over-fertilization can lead to “burning” your citrus, which you do not want.

Related: Are Your Citrus Leaves Turning Yellow?

What Kind of Fertilizers Are Food Citrus?

Citrus trees thrive in soil with high nitrogen content. Many brands produce specialty fertilizer specific to the needs and requirements of citrus plants.

If your citrus is growing as potted citrus trees, they will likely need more nitrogen than a plant grown in a landscape setting.

It’s also common for citrus trees to suffer from an iron or zinc deficiency. Applying liquid chelated iron for plants and other micronutrients can provide a quick way to deliver some much-needed iron to your soil.

How Does Fertilizer Help Citrus?

Maintaining a consistent fertilization practice helps citrus from the inside-out. It means you don’t have to treat issues topically that may occur if your citrus is lacking in nutrients and overall health.



Once a citrus plant starts taking up the nutrients through the soil the fertilizer provides, its internal defenses increase. In good health, the citrus plant can fight off fungal infections and other commonly-occurring problems better.

Identifying Common Deficiencies in Citrus

Since fertilizer helps prevent deficiencies, it’s useful to identify symptoms for common ailments that plague citrus when they lack particular nutrients.

How Can I Tell If My Citrus Has Iron Deficiency?

In plants, an iron deficiency results in chlorosis. The hallmark appearance of this condition is when the leaves on the plant appear yellow. The youngest leaves and newest growth are affected first, so it’s best to check there during your inspection.

During the early onset of symptoms, the veins of the yellowing leaves will remain green. However, as time goes on, the condition spreads further throughout the plant, the veins will also begin to yellow.

How Can I Tell If My Citrus Has Nitrogen Deficiency?

Nitrogen deficiency in citrus plants is something you want to avoid even more than an iron deficiency. Nitrogen is the most vital nutrient for a citrus tree and what you should work hardest to maintain in your plants.

When your citrus is low on nitrogen, the effects will manifest in various ways. Overall, the deficiency will stunt growth in nearly every aspect of the plant’s functions and output.

In leaves, a lack of nitrogen will cause them to grow smaller and paler than they should. They also die off and shed earlier in the season. This issue causes the stems and majority of the tree to go without protection for longer than it should, causing problems that lead to low fruit quality.

Fertilize Citrus Twice a Year

Remember to maintain a regular fertilization program with citrus fruit. Fertilize the plants twice a year, in early February and late May, and your citrus trees will grow more richly and intensely. Your citrus plants will thank you for it.

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