Fertilizer returns essential nutrients to the soil, meaning the surrounding trees and plants greatly benefit from it. As a result, fertilizer is often necessary if you want your fruit trees to grow strong, produce bountiful yields, and thrive. However, it’s essential to understand how to properly fertilize fruit trees before taking action.
Here’s how to fertilize fruit trees:
- Examine the soil.
- Examine the tree’s growth.
- Choose the right fertilizer.
- Apply fertilizer around the tree.
- Apply mulch if necessary.
- Water the area after fertilizing.
- Repeat in six months.
The rest of this article will take you through these steps in greater detail. It will also discuss other important topics regarding fertilizing fruit trees, such as the best time of year and day you should do it, the best fertilizers for fruit trees, and the best ways to encourage fruiting.
1. Examine the Soil
One of the first things you should do before applying fertilizer around your fruit tree is to check the soil. You want to be aware of the nutrient levels present in the ground, as this will determine whether or not you even need fertilizer.
To figure this out, you can carry out a soil test. You can usually get a soil test in a local garden center or at your nearest university extension service. A soil test will tell you the nutrient contents of the soil, making it easier to figure out what fertilizer–if any–you should use.
While understanding the nutrient content in your soil is essential, it’s also important to also gauge whether the texture of the earth is favorable. It’s best to have well-drained, loamy soil for fruit trees. If the soil is too dense, the roots won’t be able to grow through it as quickly.
You can add compost to the soil to amend and break it down–this is one of the best ways to turn your soil from dense to loamy. If you haven’t planted your fruit tree yet, it’s an excellent idea to carry this examination out before planting. Even if your fruit tree is already planted, you can still amend the soil and carry out a soil test.
2. Examine the Tree’s Growth
This step only applies to trees that you have already planted. While a soil test helps determine whether the soil needs fertilizer, examining your fruit tree’s growth will also help you throughout the process.
According to Iowa State University, all non-bearing fruit trees should grow between 15 and 20 inches (38 and 50.8 centimeters) annually. All bearing fruit trees should grow between 8 and 15 inches (20.3 and 38 centimeters).
Therefore, if your fruit tree grows less than the recommended amount, you likely need to fertilize it. However, you should avoid fertilizing if your tree meets the above growing recommendation (or exceeds it).
You should increase the amount of nitrogen your fruit tree receives for every year of growth. According to Oregon State University, you should begin using nitrogen fertilizer in the second year of fruit tree growth. Applying it too soon (such as during planting) can damage the roots and stunt growth.
The university also recommends using around a ¼ pound (0.11 kg) of nitrogen fertilizer in the second year. Each subsequent year, you can increase the amount by an ⅛th of a pound (0.06 kg) of nitrogen. Once the fruit tree reaches its eighth year of growth, you can stop increasing the nitrogen level and continue feeding it a pound (0.45 kilograms) of nitrogen each year.
3. Choose the Right Fertilizer
Choosing the right fertilizer is essential for your fruit tree to thrive. Firstly, consider the current situation–are you planting the tree now, or is it already established?
If you’re planting it now, you likely won’t need to apply fertilizer. You can if you want, but you should avoid using one rich in nitrogen because it can affect root growth when applied too early in the tree’s life.
As you know from the last section, you only need to use nitrogen from the second year onwards. So keep that in mind when choosing a fertilizer. Below, I’ll discuss some of the most common fertilizers you can use for fruit trees.
An organic fertilizer is an excellent choice because it doesn’t contain any chemicals that are harmful to the environment. However, it’s often not as concentrated as other types of fertilizers, so it’s only appropriate if you’re looking for a general feeder.
There are different kinds of organic fertilizer you can use, and you can make them at home:
You can work organic fertilizer into the soil around your fruit tree. Compost is a good option because it will provide your tree with plenty of nutrients and work as a soil amendment–this is helpful if your soil is too dense and retains water too easily.
You can apply an organic fertilizer to the soil once or twice a year, depending on the soil and fruit tree’s needs and conditions.
Inorganic Fertilizer (Granular)
Granular fertilizer is inorganic, meaning it contains chemicals. It’s one of the most popular fertilizer choices because you can buy it in various nutrient levels, and it’s easy to use. While granular fertilizer can be excellent for your fruit tree, you must be careful not to use too much of it–doing so can cause fertilizer burn.
You can apply granular fertilizer directly to the soil because it’s not water-soluble. There’s a wide array of varieties you can buy. For example, you can buy a granular fertilizer high in nitrogen but low in the other two macronutrients (phosphorus and potassium).
This would be good for fruit trees because they need plenty of nitrogen. However, most fruit trees would also respond well to a balanced 10-10-10 granular fertilizer. To learn more about this fertilizer, check out this article: The Complete Guide to Using Triple 10 Fertilizer
Inorganic Fertilizer (Liquid)
Another type of inorganic fertilizer you can use comes in liquid form. Liquid fertilizer isn’t the best choice for a fruit tree because you must apply it frequently. Plants and trees absorb liquid fertilizer much quicker than granular fertilizer, which is why you must use it more often.
While this wouldn’t be an issue for smaller houseplants, it’s not ideal for a plant as big as a fruit tree because it would be time-consuming. If you want to use liquid fertilizer, you’ll need to apply it once every 1-3 weeks during the growing season. On the other hand, you only need to apply granular fertilizer twice a year (in most cases).
Inorganic Fertilizer (Fertilizer Spikes)
Another type of inorganic fertilizer that is relatively popular is the fertilizer spike. Fertilizer spikes are similar to granular fertilizer because you usually only need to use them twice a year due to their slow-release nature. However, instead of spreading them, you place each spike in a hole around the tree’s dripline.
The number of spikes you should use will depend on the diameter of the dripline. The larger the diameter, the more spikes you’ll need to use. The product you buy should have instructions detailing how many spikes you should use.
If you want to use fertilizer spikes, be sure to choose ones that are aimed at trees (and, more specifically, fruit trees).
4. Apply Fertilizer Around the Tree
Once you’ve examined the soil and figured out the best type of fertilizer to use, you can apply the feeder around the tree. The most common fertilizer for trees would be granular fertilizer, and you should use it from the base of the tree across to the dripline.
As you know from earlier, the amount of nitrogen you should use will depend on the age of your tree. So, make sure you measure the fertilizer correctly before applying. When applying it to the soil, be sure to do so evenly. Using too much fertilizer in one spot can cause damage due to over-fertilization.
You should do this during early spring for the best results because it will encourage vigorous growth throughout the summer.
If using compost, you can work it into the soil surrounding the tree. When using liquid fertilizer, you can apply it to the soil around the tree’s base. You could also apply it directly to the foliage for instant absorption.
5. Apply Mulch If Necessary
Mulch isn’t necessary if weeds aren’t an issue for you and your soil is in perfect condition. However, in most cases, adding a layer of mulch around your fruit tree won’t hurt. Here are some of the benefits of using mulch around your fruit tree:
- Mulch suppresses weeds.
- Mulch retains water in the soil.
- Mulch retains nutrients in the soil.
- Mulch has insulating properties.
Since mulch helps soil retain water, you won’t need to water the soil around your fruit trees as often as usual. It also helps to control the soil’s temperature. For example, mulch will keep your soil cool in the summer and warm in the winter. It will also ensure the nutrients from the fertilizer will remain in the ground rather than get washed away or evaporated.
Mulch comes in various forms:
- Grass clippings
- Wood chips
- Rocks and stones
It’s best to apply mulch to the area after fertilization–the mulch layer may act as a barrier between the fertilizer and soil, which you want to avoid. If there is already a layer of mulch around the tree, scoop it away to apply the fertilizer. You can put it back once you’re done.
6. Water the Area After Fertilizing
Once you’ve applied fertilizer to the soil (and mulch, if applicable), you can water the area soon after. The only times you shouldn’t water after fertilization are if there is heavy rain or you use liquid fertilizer. Since liquid fertilizer is already mixed with water, adding more water may wash it away and make it less useful.
However, if you use granular or organic fertilizer, it’s good to water afterward because doing so helps push the nutrients deeper into the soil, bringing them closer to the fruit tree’s roots.
Watering will also help the mulch settle into the soil (if you apply mulch, of course). You should continue watering your fruit tree weekly to keep it healthy and hydrated. However, if it rains frequently, you may not need to water it at all. Pay attention to the weather, and give your fruit tree plenty of water during dry spells and drought periods.
7. Repeat In Six Months
Once you’ve finished the fertilization process, you should repeat it in six months. However, you’ll need to repeat the process more frequently if you use liquid fertilizer.
You won’t need to use most fertilizers more than twice a year for your fruit tree because using them too frequently can cause fertilizer burn. Most granular and organic fertilizers are slow-release, meaning they release nutrients slowly in the soil. Therefore, they survive in the ground for months before you need to reapply.
It’s best to fertilize during early spring (around March or April) and again in fall (around September or October). Fertilizing in the fall will give the fruit trees a boost and headstart for the following summer and helps them get through the winter.
When Should You Fertilize Fruit Trees?
You should fertilize fruit trees during the spring when they begin to fruit. Fertilizing at this time will give them the strength they need to thrive throughout the summer. It’s also important to fertilize during fall, giving fruit trees some additional power for the next growing season.
There’s no point in fertilizing fruit trees during winter or too late in the spring/summer. Fertilizing in winter is usually not recommended because your fruit trees will likely be dormant. And when they’re dormant, they don’t need as many nutrients and water to thrive. So the trees won’t use up the fertilizer, making the attempt wasteful.
Fertilizing too late in spring/summer is also not recommended because doing so will encourage your fruit tree to fruit later and closer to the dormant period. Therefore, you should always aim to apply fertilizer during early spring and mid-late fall.
These rules don’t just apply to fruit trees–they apply to most deciduous trees, plants, and shrubs.
What Are the Most Important Nutrients for Fruit Trees?
The most important nutrients for fruit trees are nitrogen, potassium, and phosphorus. Most fruit trees benefit from a nitrogen-focused fertilizer because it promotes healthy growth. However, potassium and phosphorus are also important because they encourage tree and root health.
While all three of these nutrients are essential for fruit trees, nitrogen is arguably the most important during the growing season. That’s why you should increase the amount of nitrogen you use each year until the tree reaches around eight years old (as discussed earlier in the article).
Nitrogen supports fruit and shoots growth, which can be essential for fruit trees. Now, I’ll discuss the three most important nutrients for fruit trees in more detail.
Nitrogen is vital for plant and tree growth. It promotes luscious green foliage and maximum fruit yields if used correctly. Without nitrogen, your fruit tree wouldn’t be able to grow or fruit to its full potential.
Your fruit tree must receive adequate levels of nitrogen. You should check nitrogen levels by doing a soil test. You can also tell if your fruit tree needs more nitrogen based on its growth rate. If it isn’t growing much yearly, it’s likely not getting enough nitrogen.
Potassium is another vital nutrient for fruit trees because it helps accelerate growth. It also helps plants with water usage. Like nitrogen, your fruit tree also wouldn’t thrive without enough potassium. Thankfully, potassium occurs naturally in the soil. And if there isn’t enough of it in the ground, you can easily find a fertilizer that supplies it.
According to the University of Nebraska-Lincoln, phosphorus promotes healthy root growth in plants and fruit trees. The university also states that phosphorus helps plants remain hardy during winter, meaning your fruit tree will be less likely to get frost-damaged.
Therefore, your soil must contain the proper levels of phosphorus. If it doesn’t, be sure to choose a fertilizer with plenty of phosphorus.
How To Use Granular Fertilizer in Fruit Trees
Earlier, I mentioned that granular fertilizer is one of the most popular choices for fruit trees. One of the reasons why it’s such a popular choice is that it’s relatively easy to use and gives your fruit trees and plants precisely what they need. But it’s good to know exactly how to use granular fertilizer. Misusing it may result in over or under-fertilization.
Here is a brief guide on how to use granular fertilizer in fruit trees:
- Make sure it provides the correct ratio of macronutrients. Firstly, you want to ensure the fertilizer provides the proper ratio of nutrients to the soil. For example, if your soil needs extra nitrogen, ensure the fertilizer contains higher nitrogen levels.
- Read the instructions. Before applying fertilizer to the ground, you should read the instructions on the fertilizer packaging. In some cases, it might tell you how to fertilize trees.
- Apply the granules evenly around the dripline. You want to apply an even layer of fertilizer around the fruit tree’s dripline. Avoid using a too thick layer–this may result in burning and could seriously affect your fruit tree’s health and growth.
- Water the soil directly after fertilizing. When using a granular fertilizer, it’s good to water the area soon after fertilizing. It helps the fertilizer mix in with the earth to reach the roots more easily. Fertilizer can burn the soil if left at the surface (especially in hot weather).
How To Use Liquid Fertilizer in Fruit Trees
Now that I’ve explained how to use granular fertilizer, I want to explain how to use liquid fertilizer in fruit trees. Generally, it’s not good to use liquid fertilizer on any tree because you’ll need to apply it frequently, making it a high-effort activity.
However, below is a brief guide on how to use liquid fertilizer in fruit trees:
- Make sure the fertilizer is the right type for your needs. Like any fertilizer, you should ensure your liquid fertilizer has the correct level of nutrients before using it.
- Read the instructions. Most liquid fertilizers will have instructions on the packaging, so check and follow those if you can.
- Mix the fertilizer with water. The packaging should tell you how much water to mix with the fertilizer. Generally, you should mix one gallon (4.5 liters) of water with 1-2 teaspoons (4.93-9.86 ml) of fertilizer.
- Apply the fertilizer around the tree’s dripline. You can apply the fertilizer around the drip line as if watering the soil.
- Apply the fertilizer to the tree’s foliage. While you can’t apply granular fertilizer directly to the foliage of your fruit tree, the liquid variety offers this possibility. It allows the tree to absorb nutrients quickly.
According to Clemson University, applying liquid fertilizer to a plant or tree’s foliage only acts as a temporary solution. For a better, longer-term solution, you should get a soil test and apply granular fertilizer to the surrounding soil.
Best Organic Fruit Tree Fertilizers
If you want to use organic fertilizer instead of inorganic, it’s good to know your options. Luckily, there are different types to choose from, and each one is highly beneficial for fruit trees. The best organic fruit tree fertilizers should contain all essential macronutrients. They should also include a wide array of micronutrients.
Below are some of the best fruit tree fertilizers.
Fish emulsion is usually made from leftovers or parts of fish you don’t want to consume. Thankfully, the fish emulsion contains all three essential nutrients for fruit trees (nitrogen, phosphorus, and potassium).
You can make fish emulsion at home, so it’s cheaper than buying inorganic products. All you need is molasses and organic waste, like grass clippings. I’ve written an extensive guide on how to make homemade fish fertilizer. Don’t miss it: How to Make Homemade Fish Fertilizer (DIY Guide)
An important element to note about fish emulsion is that you’ll need to leave it to sit for a few weeks before using it. So if you plan on making fish emulsion for your fruit trees, prepare it a few weeks before the fertilization date.
It’s best to use fish emulsion once every 2-3 weeks during the growing season because it’s fast-releasing.
Soybean meal is suitable as a fruit tree fertilizer because it contains high nitrogen levels. While it also contains phosphorus and potassium, the levels are negligible. So if your soil is lacking in one of those, you may want to consider a different fertilizer.
Although soybean meal is commonly used to feed animals, it can feed plants too. You can make it at home, which can save you money on fertilizer.
You can use soybean meal once every 1-2 months during the growing season, so you must apply it more frequently than standard granular fertilizer.
Blood meal is animal blood, and it’s excellent for fruit trees because it contains essential nutrients like protein. However, this is one of the few organic fertilizers you usually can’t make at home. You’ll need to buy it from a store, but luckily, most garden stores and centers should supply blood meal fertilizer.
It’s easy to use–you can apply it directly to the soil around the fruit tree or mix it with water.
Best Inorganic Fruit Tree Fertilizers
Now that you know more about some of the best organic fertilizers for fruit trees, you may want to learn more about the best inorganic fruit tree fertilizers as well.
- Fruit Food Spikes. Fruit tree spikes are excellent for fertilizing fruit trees. You can hammer these directly into the soil. You don’t need to mix or take any measurements–just remove the spikes from the packaging and use them as the manufacturer’s instructions require.
- Citrus Fruit Tree Food. This fertilizer works well with citrus, fruit, and avocado trees. It contains a slightly higher level of nitrogen (most fruit trees will benefit from higher nitrogen levels) and usually comes in granular form. Since it’s a granular fertilizer, you can apply it directly to the soil and don’t need to dilute it with water. However, it’s still best to water the area right after. You can use this fertilizer twice per year.
- 10-10-10 Fertilizer. This fertilizer is excellent if you’re looking for a general, all-purpose feed for your fruit trees. You should use it if your soil needs equal amounts of all three macronutrients. However, if you want to use a fertilizer higher in nitrogen, you might want to consider a different NPK formulation.
Signs of Over-Fertilization in Fruit Trees
While fertilizing can greatly benefit fruit trees, it can also be detrimental if you do it incorrectly. If applying fertilizer to your fruit tree, you should always look for signs of over-fertilization.
Therefore, you can fertilize less frequently to prevent the problem from worsening.
Below are the main signs to look out for in cases of over-fertilization:
Visible Fertilizer on the Soil
One significant sign of over-fertilization is when you can visibly see fertilizer on the soil–this means you’ve likely applied too much product, and the ground is now suffering. To try and fix the problem, you should scoop out as much visible fertilizer as possible. Once you’ve removed as much affected soil as possible, you can mix compost into the ground.
You can also water the soil to wash out as much fertilizer as possible.
Another sign of over-fertilization in fruit trees is discolored leaves. They may turn brown and yellow as the health of the fruit tree declines. However, discolored leaves can also be a sign of other issues like:
- Root rot
If you think the discolored leaves are occurring due to over-fertilization, stop fertilizing the fruit tree immediately.
Pennsylvania State University states that wilting leaves are a sign of over-fertilization in potted plants, and you can say the same for other plants (like fruit trees). If you notice droopy leaves, you should rule out over-fertilization before fertilizing again. The leaves on fruit trees should be firm and vibrant, so it’s never normal for them to appear wilted.
Stunted growth is another well-known symptom of over-fertilization, but it can be a sign of many other issues as well. Any plant or fruit tree experiencing troubles is likely to have stunted growth.
However, this situation can be tricky because stunted growth also indicates that your fruit tree needs more fertilizer. If you have fertilized your fruit tree generously but are suddenly noticing stunted growth, it’s likely because you have over-fertilized it.
If your fruit tree lacks fruit, there is a chance you have over-fertilized it. Over-fertilization can harm the tree’s roots, and if the roots are damaged, they won’t be able to support the rest of the tree. Therefore, the tree is less likely to produce fruit.
So if you’ve recently fertilized and noticed a lessened yield, you may have over-fertilized without realizing it. Be sure to stop fertilizing until you remedy the issue.
How To Encourage Fruiting in Trees
Since you’re reading this article, you probably understand that fertilizing fruit trees is an excellent way to encourage fruiting. However, other approaches are equally important if you want your tree to produce as much fruit as possible. Fertilizing alone isn’t enough.
Along with fertilizing, below are some excellent ways to encourage fruiting.
Ensure the Soil Is in Good Condition
One of the keys to healthy fruiting is having suitable soil. Your fruit tree won’t be able to thrive if the soil is too dense and saturated. It might have trouble growing at all if this is the case. So to ensure your tree can thrive as much as possible, ensure the soil is loamy and well-draining.
You want the soil to be loose and light enough that the roots, fertilizer, and water can flow through it seamlessly without retaining too much excess. If you apply fertilizer to soil that’s too dense, it will retain it for longer. It may seem reasonable, but this leads to a higher risk of over-fertilization.
Fertilize if Necessary
Fertilizing is an excellent way to promote fruiting in trees, and most trees will benefit from some form of fertilizer. However, certain soils may have sufficient levels of the necessary nutrients–in this case, you might not need any fertilizer.
Hopefully, you know more about fertilizing fruit trees from reading the article to this point. The most important thing to remember is that granular fertilizer is generally the best for fruit trees (although spikes can also work well).
The best fruit tree fertilizers are usually balanced ones (such as 10-10-10 fertilizer) or more nitrogen-focused fertilizers (particularly for soil that naturally lacks sufficient nitrogen).
You should ensure your fruit trees always receive enough water throughout the growing season. The fruit trees can become dehydrated and scorched if they are in the sun all day and don’t receive adequate levels of water.
There’s no use in fertilizing your fruit tree if you’re not going to give it enough water to stay hydrated.
If it rains in your region, you might not need to water your fruit trees. But if you live somewhere hot and dry, be sure to water your fruit trees generously once a week. Watering after fertilization is also necessary because it helps push the fertilizer deeper into the soil.
Prune During Dormancy
Although you don’t need to fertilize your fruit trees during dormancy, it’s good to prune them during this period. One benefit of pruning during dormancy is that there are no leaves or fruits in the way, making it easier to see what you need to cut away.
Pruning during dormancy will also help your fruit tree gain new growth during the next growing season. You should remove the weakest branches so that fresher, healthier ones can come in during the following spring and summer.
Most dormant periods occur during winter, so this is an excellent time to prune fruit trees.
Keep Pests Away
If your fruit tree is to thrive, you must keep pests away. Pests are a nuisance and can eat away at your tree and fruit. Unfortunately, fertilizer alone can’t prevent pests, so taking other preventative measures is essential.
Here are some ways you can keep pests away from your fruit trees:
- Keep your fruit tree strong by fertilizing. Although fertilizing alone can’t keep pests away from your fruit tree, it can certainly help. If your tree is healthy and has all the essential nutrients, it will be better equipped to fight off pests.
- Use repellents. The University of New Hampshire recommends using some of the following: fungicides, insecticides, or multipurpose sprays. The specific product will depend on the pest you’re trying to keep away.
- Prune. Another helpful solution is to prune your fruit tree. Doing so will keep it tidy. A messy tree with lots of branches will easily harbor pests without you even noticing. As mentioned in the last section, prune during winter when your trees are dormant.
- Use Epsom salt. You can mix Epsom salt with water and apply it every few weeks to deter certain pests and bugs.
Best Time of Day To Fertilize Fruit Trees
The best time of day to fertilize fruit trees is in the morning before the temperatures get too hot. If you apply fertilizer in the middle of the day, you’ll risk burning your soil and fruit trees. Fertilizing in the morning gives the fertilizer a chance to settle while the temperature is cooler.
The next best time of day to fertilize your fruit tree is in the evening because the temperatures will have cooled down again, meaning the soil and plants are less likely to burn.
If you’re going to fertilize in the morning, do so early enough. Once it reaches 8 or 9 am, the temperature may already be too hot.
When fertilizing in the evening, wait until at least 5 pm. If it happens to be a scorching day, you may want to do it even later than this.
Is Epsom Salt Good for Fruit Trees?
Epsom salt is good for fruit trees and many other plants because it contains magnesium. So, you should use Epsom salt if your soil and fruit trees are lacking in magnesium. It’s easy to use Epsom salt as fertilizer–all you need to do is mix a teaspoon with a gallon (4.5 liters) of water.
According to the Epsom Salt Council, Epsom salt can do the following:
- Help seeds germinate.
- Make plants (and trees) greener and bushier.
- Provide nutrients.
Is Compost Good for Fruit Trees?
Compost is good for fruit trees because it feeds them slowly over a long period. Therefore, you only need to apply it once or twice annually. It also improves soil quality and is cheaper than buying inorganic fertilizer online or from a garden center.
Moreover, compost contains all the essential macronutrients your fruit tree needs. However, if your fruit trees and soil need specific levels of certain nutrients, it might be better to use an inorganic fertilizer instead of compost.
Fertilizing fruit trees is a quick and straightforward process, but there’s a lot of information to be aware of before you get started.
After reading this article, you should have a better understanding of the following:
- How to fertilize fruit trees.
- The different types of fertilizers for fruit trees.
- The best times to fertilize fruit trees.
- Signs of over-fertilization in fruit trees.
Before adding any fertilizer to your soil, it’s best to do a soil test to check what nutrients are most needed.