How and when to fertilize lime tree
Lime tree, or by its scientific name Citrus aurantifolia, are one of the most popular citrus fruits in gardens around the world. Although on many occasions it is difficult to differentiate it from its first cousin, the lemon tree, of which not only does it share morphological similarities but its care is also very similar, including fertilization. But there are always some differences, so this time we will take care of talking about everything related to the use of fertilizer in lime tree. We will already have the opportunity to dedicate a special article to the lemon tree.
Although it is customary in this blog to begin each of the articles with a first section where the necessary care for the plant in question is discussed, this time we will break with this custom (which I think is not the first time that happens). Given the great confusion that exists, we prefer to clarify what are the most notable differences between the lemon tree and the lime tree. In the event that in the future we write about the lemon tree, we will dedicate the first section to the care of these citrus fruits, which are practically the same as those of the lime tree.

Table of Contents
1. Differences between the lime tree and the lemon tree
How are you going to take care of a plant if from the beginning you are not even sure what plant it is. I do not blame you if you are not clear if what you have planted in your garden is a lime tree or a lemon tree, maybe in the nursery they sold you the wrong plant, and you planted what you thought was a lemon tree and it turned out a lime tree.
Whatever the case, do not make any problems. With the simple tips that we will see below, you will become an expert in differentiating these two popular citrus fruits.
- Although it may be somewhat relative, the first thing you notice is the size of the tree. If it is a tree of about 5 or 6 meters, it is surely a lemon tree, since lime tree generally do not exceed 4 meters.
- If with the size you have not been able to define what citrus it is, you can go on to observe the leaves. That again those of the lemon tree are larger, with average dimensions of between 10 and 13 cm, while the lime leaves do not exceed 8 cm.
- If comparing the sizes of the plant and its leaves, you still have doubts, we will go on to verify certain aromas of the plant. In the case of leaves, the aroma in lemon trees is mild, while lime leaves have a strong aroma. Now take some rind, the lemon tree has no smell, while the lime has a strong citrus smell.
Well, I hope that with these three tips you have been able to detect what citrus fruits you have at home. Now, if it is a lime tree, I recommend that you continue reading this post.
2.What are NPK values in a fertilizer
In each and every one of the articles on this blog where we talk about fertilization, we need to clarify what NPK values are. We do this because there are a lot of novice gardeners who pass by and are not clear on this concept. If you are clear about what these three numbers are about, you can skip this short section.
The NPK values represent the concentration by weight of the three main nutrients in the fertilizer. For example, a 15-25-10 fertilizer is composed of 15% by weight of nitrogen, 25% by weight of phosphorus and 10% by weight of potassium.
The NPK values represent the concentration by weight of the three main nutrients in the fertilizer.
And you may wonder why these nutrients are so important, basically because of the following:
- Nitrogen (N): it is undoubtedly the most popular nutrient and helps to produce leaves and maintain a good green color.
- Phosphorus (P): this nutrient helps to form new roots, produce seeds, fruits and flowers. Its application also helps plants fight diseases.
- Potassium (K): helps plants develop strong stems and maintain rapid growth. It is also used to fight diseases.
Depending on what plant it is, it may need different concentrations of these nutrients to develop properly, which is why there is so much variety of fertilizers. Let’s see below which are the best fertilizers to apply on lime tree.
3. Best fertilizer for lime tree
The first thing you should do before making a fertilization plan is to define what types of fertilizer you are going to use in your lime tree. When I say types, I mean the two main groups of fertilizers, which are commercial chemical fertilizers or organic fertilizers. You can use only chemical fertilizers for your lime plants or fertilize only with organic fertilizers. Although from this website we always recommend mixed fertilization plans, taking advantage of the benefits of both types of fertilizers.
If what you are going to apply are organic fertilizers, the most common is to apply compost and / or animal manure. In both cases, the most important thing is to verify that they are correctly fermented. Unfinished compost or manure can cause multiple problems for your plants. In a good fermentation the material has a uniform color and little odor.
From this website we always recommend mixed fertilization plans, taking advantage of the benefits of commercial fertilizers and organic fertilizers.
If you apply commercial fertilizers, depending on the age of the plant, you can use different types of fertilizers (we will discuss this in the next section). Among the mixtures that may be useful are balanced 8-8-8 (same concentration of the three nutrients), and mixtures with higher concentration of nitrogen and potassium such as 12-0-12.
You will see that when you go to buy a fertilizer they will offer it to you in different formats, they can be liquid, granulated, stick, powder, etc. The important thing is to define if it is fast or slow release, that is, if it releases nutrients quickly (a liquid fertilizer) or slowly (in a stick). In the case of a citrus fruit such as lime, the ideal commercial fertilizer is one that slowly releases the nutritive agents, since it does not need the concentrated nutrients at any given time.
If you are reading this post, you will probably be interested in learning about fertilizing these other plants.
4. How and when to fertilize lime tree
As with the fertilization of any plant, it is not enough to know what fertilizers you need to apply, but you must also be clear about how and when to apply them. We will discuss that in this section.
4.1 When to fertilize
Fertilization in all fruit trees goes hand in hand with the cycles of the plant. Cycles of growth, flowering, fruiting, harvesting. Nutrient needs are different at each stage.
As a general rule, you should know that it is not good to start with fertilizations when the lime tree is too small. It is easy to exceed the necessary dose of nutrients in very young plants, which can cause irreparable damage. Therefore, wait until the seedling is at least 20 cm before applying any fertilizers.
It is not good to start with fertilizations when the lime tree is too small, exceeding the dose is something very easy.
When what you have are adult lime trees, it is good to divide the fertilization into three times of the year. You can do the first fertilization in late fall or early winter. Then the most important fertilization is the one you will carry out in early spring (when the plant begins to sprout), and you will finish with the fertilizations in the last days of summer.
These fertilization times may not be fixed and will go hand in hand depending on the type of fertilizer you use. For example, there are slow-release fertilizers that take up to 12 months to release all the nutrients. So it may be that the application of a single annual fertilizer was sufficient to cover all the nutrient needs of the lime.
4.2 How to fertilize
You are now able to differentiate a lime tree from a lemon tree, you have learned which are the most useful fertilizers for this citrus and when to fertilize. Let’s now see how the fertilization process should be carried out.
Let’s start talking about young plants of lime tree, calling those plants of more than 20 cm young until the age when they begin to bear fruit. In these cases, balanced fertilizers (eg, 8-8-8) or an organic fertilizer such as manure or compost are recommended. The fertilization process does not change whatever the type of fertilization, the soil must be moved a little in a ring about 80 cm wide, keeping it away from the stem. Then apply the fertilizer evenly and accompany a good watering.
In very young plant of lime tree, which do not exceed 40 cm, the application of nitrogen fertilizers that quickly release their nutrients (for example, a liquid fertilizer) should be avoided, especially if rain is forecast.

When what you have are adult plants, the fertilization process is similar. Unlike what happens in the production stage, it is good to replace balanced formulas with one with a higher concentration of nitrogen (for example, 12-0-12). Then we can put together a fertilization plan in an adult plant like the following:
- First fertilization: In late autumn or early winter apply an organic fertilizer. An approximate dose that you can use is 1 kg of compost for each plant. The application should be made at a distance of about 30 cm from the trunk in a ring equal to that described in previous paragraphs.
- Second Fertilization: Use a 12-0-12 commercial mix fertilizer and apply in early spring. Look for a slow release one in 3 months, so we can do a last fertilization. The dose will depend on the fertilizer instructions, and the method will be with the ring around our lime tree.
- Third fertilization: in this case we will use a slow release 8-8-8 balanced fertilizer that we will apply at the end of the summer, the application will be the same as the previous ones.
Always try to accompany each fertilization of your lime tree with a good watering. And of course, never stop reading the instructions on the fertilizer bottles.
5. Extra cases
Although the articles on our blog are always quite general, since it is never possible to cover all the variants that may arise in the care of a plant, but sometimes when a query is repeated we like to spend time to clarify it. In the case of lime trees, we find two questions that we want to answer, and they are the following:
4.1 How do I fertilize a key lime?
To answer this question, it must first be clarified that the key lime is one of the many names that Citrus aurantifolia has. Among others we can find West Indian lime, bartender’s lime, Omani lime, or Mexican lime. It should also be noted that it is very difficult to identify what is called key lime in the country where you live. Depending on what English-speaking country you are in, they might say something different than what in the US they call it key lime.
Without delving into those technicalities of language, you should know that everything we saw in this post applies to a key lime tree. So if you have that citrus in your garden you can follow all the advice seen so far.
4.2 How do I fertilize a indoor lime tree (potted)?
Answering this question is even easier than answering the previous one. With the difference that I must recommend that if you want your lime tree not to exceed in size you should reduce the dose and regularity of fertilization.
On the other hand, if you have your indoor lime tree, you may not want to apply smelly fertilizers. In that case, you may always need to check that point before applying a fertilizer like manure, which can smell a lot if it’s not 100% fermented.
5. How to grow your limes trees (video)
To finish, and since this time we do not dedicate a section to see the care of the lime tree, we have selected a video (Self Sufficient Me channel) where this question is analyzed. Look at it because I have no doubt that you will be able to get a lot out of the information that they give there.
To finish this post I leave you some links that may be interesting for you to learn more about the cultivation of a lime tree.
- Key Lime Growing in the Florida Home Landscape – edis.ifas.ufl.edu.
- Growing Citrus Indoors – mastergardener.extension.wisc.edu.
- How to grow and care for limes – lovethegarden.com.