The 11 Most Effective Fruit Tree Fertilizers (All You Need to Know About Fertilizing Trees)

The 11 Most Effective Fruit Tree Fertilizers (All You Need to Know About Fertilizing Trees)

Growing your own fruit is an experience that we think everyone with enough garden space should try. It’s super rewarding and a fun process that helps to keep you in touch with nature and the four seasons. 

The problem is, a lot of people – even seasoned gardeners – shy away from growing fruit trees because they believe it will be too difficult to provide the trees with the consistent nourishment they need to thrive. 

Thankfully, with the right fertilizer, you can easily nourish your fruit trees in just a few minutes without having to do anything complicated to the soil. 

In this guide, we’ll be recommending and reviewing our 11 favorite brands of fruit tree fertilizer and guiding you through the process of fertilizing your fruit trees. From when to apply fertilizer to the soil, to which type of fertilizer will be best for your trees, we’ve got you covered! 

The Top 11 Fruit Tree Fertilizers

Dr. Earth 708P Organic 5-5-2 Fruit Tree Fertilizer


The Dr. Earth Organic 5-5-2 Fruit Tree Fertilizer is undeniably one of the best on the gardening market, for a few different reasons. 

We’ve personally used this TruBiotic formula and can confirm that the combination of mycorrhizae and microbes (all of which are totally organic) really help fruit trees to develop strong and stable roots. 

Since there are no filler ingredients in this formula, you can trust that it’s natural and doesn’t contain any potentially damaging chemicals or GMOs.

Because of this, the Dr. Earth 5-5-2 fertilizer can be applied to the soil around your fruit trees without risking harm to any passing wildlife, pets, or people. 

The formula doesn’t contain any manure, which means that unlike some of the fertilizers on the market, the odor isn’t pungent or overpowering.

With that being said, there are no ingredients in the fertilizer to disguise the natural odor, which can take a little while to get used to if you’re not accustomed to working with fertilizers.


  • Made with probiotic – Great for strong roots 
  • No filler ingredients – Natural formula 
  • Free from manure – Odor is not overpowering 
  • Non-toxic when applied – Not damaging to wildlife, pets, or humans 


  • Natural smell – The odor can take some getting used to

EarthPods Premium Fruit & Citrus Plant Food


If you’re growing citrus fruit trees, you might be interested in the EarthPods Premium Fruit & Citrus Plant Food capsules. 

This is another all-natural formula, so you don’t need to worry about filler ingredients or damaging chemicals.

This fertilizer won’t cause root burn, which is a major concern with some of the less natural formulas out there. 

Because the EarthPods Premium fertilizer comes in capsule form, it takes a lot of the work out of fertilizing your fruit trees because you don’t have to measure anything out.

All you need to do is press the capsules into the soil around the tree’s roots and water. You will need to do this every 2 or 3 weeks, though, which is more than a lot of fertilizers require.

This means you might need to buy EarthPods fertilizer more often than other brands.

Since this fertilizer doesn’t emit any pungent odor, you can use it for plants you’re growing indoors, although it’s also totally suitable for outdoor growing. 

Something we love about the EarthPods Premium fruit tree fertilizer is the fact that the packaging is so eco-friendly, producing zero waste. 


  • All-natural formula – Safe and healthy 
  • Capsule push application – No measuring 
  • No odor – Ideal for indoor growing 
  • Eco-friendly packaging – Zero waste 


  • Needs applying frequently – Regular repurchasing needed 

Down To Earth Organic Fruit Tree Fertilizer Mix 6-2-4


For those who are looking for fruit tree fertilizers that have been certified organic by the OMRI, we recommend the Down to Earth Organic Fruit Tree Fertilizer Mix 6-2-4. 

In addition to being certified organic, meaning it contains natural and safe ingredients, the formula is made with extra calcium.

The extra calcium has been added for the purpose of speeding up fruit growth and producing larger fruit in higher quantities. 

One thing that we love about this formula is the fact that while it’s perfect for growing fruit trees, it can also be applied to a wide variety of plants, including shrubs and potted plants. This means you don’t need to worry about finding a different fertilizer for all your plants. 

Additionally, Down to Earth makes using this fertilizer easy for complete beginners because it provides instructions for applying the formula to different fruit trees on the packaging.

This will save you time you might otherwise have spent researching the optimal dose for individual fruit trees. 

With that being said, we did notice that certain trees may need more fertilizer than the stated dose, so treat the instructions as guidelines and pay attention to the growth of your trees to determine how much they need. 


  • OMRI organic certification – Natural and safe 
  • Contains extra calcium – Speeds up fruit growth
  • Suitable for various plants – Highly versatile 
  • Fruit-specific instructions on packaging – Beginner-friendly 


  • Some trees might need more than the stated dose – Measurements are just guidelines 

Down To Earth Organic Citrus Fertilizer Mix 6-3-3


Another fertilizer mix by Down to Earth that we recommend specifically for citrus fruit trees is the Organic Citrus Fertilizer 6-3-3 formula. 

Like the last Down to Earth fruit tree fertilizer we reviewed, this one has been certified organic by the OMRI, so it’s organic and safe for the surrounding environment.

However, you need to make sure to scratch it well into the soil when applying it because the fishbone meal in the formula can attract pets and wildlife and may cause digestive issues.

Another similarity between this fertilizer and the previous Down to Earth fertilizer is the fact that it’s so versatile.

While the formula is primarily designed for citrus trees, it can also be used to grow healthy nut trees and other types of fruit trees. 

The formula is made up of natural meals, including fishbone meal, feather meal and alfalfa meal as well as basalt and greensand. All of these ingredients are natural, making this a natural formula overall.


  • OMRI certified – Organic and eco-friendly 
  • Made with natural meal, basalt and greensand – All-natural
  • Suitable for citrus, nut, and other fruit trees – Versatile application


  • Not suitable for pet consumption – Needs scratching into soil 

Fertilome 10820 Citrus And Pecan Tree Food 19-10-5


If you grow both fruit and nut trees in your garden, including citrus trees, the Fertilome 10820 Citrus and Pecan Tree Food 19-10-5 will be perfect for your gardening needs since it’s very versatile. 

The granule formula of this fertilizer is easy to apply because it can be spread in an even layer for optimal absorption.

Even application across all the roots is really important, especially since the fertilizer is high in zinc, which helps to protect your trees from rosette disease. 

We also love that this fertilizer doesn’t produce any organic odors, so if you’re growing any trees indoors, you can use the fertilizer without worrying about filling the room with pungent smells. 

Unfortunately, this fertilizer comes at a higher price point than some of the other choices we’ll be recommending today, so if you’re looking for something budget-friendly, you might want to consider other options. 

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  • Granule formula – Easy to spread evenly 
  • High in zinc – Prevents rosette disease 
  • Works for fruit, nut and citrus trees – Very versatile
  • Organic odor-free – Pleasant to work with 


  • High price point – Not budget-friendly 

Espoma TR4 Tree-Tone 6-3-2 Plant Food


There are a couple of different fertilizers from Espoma we want to recommend today, but the first one is the TR4 Tree-Tone 6-3-2 Plant Food. 

We especially recommend this fertilizer if you have trees in your garden that are unhealthy or not growing well since this formula provides a slow but highly effective release of nutrients, which will soon perk up ailing fruit trees. 

The formula is versatile enough to be used on both ornamental trees and trees that require full sunlight exposure.

With that being said, it needs to be applied to well-draining soil, so it’s not suitable for trees that are being grown in pots, even if the pot has draining holes. This fertilizer is exclusively for outdoor use. 

Since this is a slow-release fertilizer, you only need to apply it twice a year, so it’s low-maintenance to work with and won’t need re-purchasing very often. 


  • Slow-release nutrition – Only needs applying twice a year 
  • Suitable for ornamental and full-sun trees – Versatile 
  • Effective nutrient replenishment – Ideal for unhealthy trees 


  • Not for use on trees in pots – Only suitable for outdoor growing

Espoma Organic Citrus-Tone 5-2-6 Natural Fertilizer


The other fertilizer by Espoma that we like to use for citrus fruit trees is the Organic Citrus-tone 5-2-6 Natural Fertilizer. This is one of the best fertilizers out there, especially if you want your citrus fruits to taste as good as possible. 

The presence of the Bio-Tone microbes ensures that the citrus fruits you grow will be bursting with delicious flavor.

Meanwhile, the 5-2-6 NPK nutritional balance will help your trees to produce more fruit and grow healthier-looking, stronger leaves. 

Because this is a slow-release formula that comes in granular form, you don’t need to apply it very often, so keeping your fruit trees strong and healthy doesn’t have to be an arduous task. 

Bear in mind, though, that this fertilizer’s efficacy is easily affected by over-watering.

If you over-water your trees after applying this fertilizer, you may need to apply it more frequently, which would add more maintenance and expense to the process. 


  • Made with Bio-Tone microbes – Improves fruit flavor 
  • 5-2-6 NPK – Increases yield and produces healthy leaves 
  • Slow-release formula – Needs applying infrequently 


  • Efficacy can be reduced by overwatering – Requires careful water measurements 

Jobe’s Organics 01213 Tree Spikes


Jobe’s is one of the most popular fertilizer brands, and that’s why we have 3 different Jobe’s fertilizer formulas to share with you today. To start with, we’d like to recommend the amazing Jobe’s Organics 01213 Tree Spikes. 

Although it’s one of the most popular and effective fertilizers for fruit trees, it’s also one of the more affordable options, so if you’re gardening on a budget, we highly recommend it. 

We love that this is a slow-release formula that only needs one seasonal application because it takes a lot of the hard work and maintenance out of the equation.

Despite infrequent application, you’ll see a big difference in the health and yield of your fruit trees due to the 8-2-2 NPK balance which delivers a lot of nitrogen to the tree roots for a higher yield of fruit. 

As well as using this fertilizer to grow your fruit trees, you can also apply it to nut trees, so it’s versatile. 

The only thing to bear in mind is that since you’ll only be applying this formula once per season, you may have a bag in storage for a long time depending on how many trees you’re growing.

This fertilizer can be easily damaged by excess humidity and high temperatures, so make sure to store it somewhere cool and dry. 


  • Low price point – Budget-friendly 
  • Slow-release – Only needs applying once per season
  • 8-2-2 NPK balance – More nitrogen for higher yield 
  • Suitable for fruit and nut trees – Multipurpose 


  • Can be damaged by heat and humidity – Needs specific storage conditions

Jobe’s 01612 Fruit & Citrus Fertilizer Spikes


The second fertilizer by Jobe’s that we think citrus and other fruit tree growers will appreciate is the 01612 Fruit & Citrus Fertilizer Spikes formula. 

This is one of the few fertilizer formulas that can be used on both potted plants indoors and outdoor trees that are rooted directly into the ground. This makes it a versatile choice. 

It’s also a safe choice because the formula is natural and doesn’t contain any ingredients that could be harmful to either wildlife or pets in your garden.

Many gardeners worry about animals accidentally being harmed by their fertilizer, but with Jobe’s Fruit & Citrus Fertilizer Spikes, this isn’t something you need to be concerned about. 

Thanks to the 3-5-5 NPK balance, your fruit will grow faster and your soil will be healthier and able to deliver better nutrition. 

Just remember that this fertilizer doesn’t have a long shelf life. It needs to be used within the season because it won’t keep for longer than this, so pay attention to the quantities you’re buying at the time of purchase and make sure it’s not too much more than you’ll need for a season.


  • For indoor and outdoor use – Versatile 
  • Eco-friendly and pet-safe – No risk to wildlife 
  • 3-5-5 NPK – Good for soil health and fast growth


  • Single-season shelf life –  Package must be used at once 

Jobe’s Organics 9227 Fruit & Nut Granular Fertilizer


The final Jobe’s fertilizer we think you should be aware of, especially if you grow both fruit and nut trees, is the Fruit & Nut Granular Fertilizer. 

This formula has a 3-5-5 NPK ratio, which means it’s lower in nitrogen than many of the fertilizers on the market for fruit trees.

While nitrogen is important for nourishment, the lower ratio of nitrogen to other nutrients is actually ideal for lush foliage. 

Additionally, this is a versatile fertilizer that can be used to feed fruit and nut trees both rooted into the ground or in containers. 

Since this fertilizer has a fairly long shelf life, we like that it comes in resealable packaging that not only makes it easy to pour out the granules accurately but makes long-term storage easier. 

Just be wary of over-fertilizing since this is likely to reduce your yield rather than help the growth of your trees.


  • 3-5-5 NPK – Low nitrogen for lush foliage 
  • Suitable for container and ground growing – Versatile application
  • Resealable packaging – Easy to store 


  • Risk of reducing fruit yield by over-fertilizing – Careful measurements required 

Miracle-Gro Fruit & Citrus Plant Food Spikes


Miracle-Gro is a well-known gardening brand, and the Fruit & Citrus Plant Food Spikes formula is one of our all-time favorites for growing robust and healthy fruit trees. 

This is a natural fertilizer formula which is safe for the environment and any wildlife in your garden. It’s also affordable, so you can use it regularly even if you have a tight gardening budget. 

With an NPK balance of 15-5-10, which promotes excellent fruit yields, applying it is really easy thanks to the convenient spikes and plastic caps included with the purchase. However, keep in mind that the spikes are quite fragile and can be easily broken, so handle them with care before and during use.

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  • Natural formula – Good for the environment and wildlife 
  • Affordable – Suitable for budget gardening 
  • 15-5-10 NPK – Promotes higher yields 
  • Spike application – Easy to use 


  • Spikes are fragile – Must be handled with care 

The Best Time to Fertilize Fruit Trees (According To Species)

Fertilizing your fruit trees is important if you want them to be as robust and plentiful as possible, and if you want your fruit to taste amazing.

However, fertilizing certain trees at the wrong time or with the wrong level of frequency can actually do more harm than good. 

Here’s when you should fertilize different kinds of fruit trees for the best results: 

Citrus Trees

The umbrella of ‘citrus trees’ refers to any trees that produce citrus fruits, such as lemons, limes, and oranges.

You’ll notice that we have a few citrus-specific fertilizer blends in our review section, and that’s because citrus trees often have specific nutritional needs. 

Additionally, you will need to feed citrus trees at a different frequency compared to other fruit trees.

That’s why many manufacturers that produce versatile fertilizer blends for citrus trees and other types of trees often provide different instructions for the various tree species on the packaging.

Usually, citrus trees only need to be fertilized once per season, especially since they’re more often grown in warm climates.

You should start feeding these trees in late winter, then again during the spring once you notice the flowers coming through. The third fertilization should come around summer, in late July or August. 

Apple Trees

Apple trees are some of the most commonly grown fruit trees worldwide, so many gardeners want to know how to fertilize these trees.

Like citrus trees, apple trees need to be fed around three times per year. However, unlike citrus trees, you don’t want to start fertilizing during the winter.

Instead, give your apple trees their first feed in spring before they flower. After that, you should wait for them to flower before giving a second feeding. 

You may also want to feed your apple trees during the summer, but this isn’t always necessary. Watch the growth of the trees to see if they look healthy and are producing healthy foliage as expected.

If not, fertilize again, but if so, don’t add any more fertilizer since excess nitrogen will compromise rather than encourage growth. 

Banana Trees

Like citrus trees, banana trees grow best in temperate climates. This is important to bear in mind when considering how often to fertilize your banana trees.

You should usually fertilize banana trees during the first months of spring, and not fertilize again for the rest of the year.

It’s best to use a banana-specific fertilizer that is rich in potassium once the flowers start coming through since this will be better for the foliage. 

Fig Trees

If you’re growing fig trees, you’ll know that the flavor of the fruit is as important as anything else, and you’ll need to choose both your fertilizer and feeding schedule accordingly. 

Luckily, fig trees are pretty low-maintenance because they grow so slowly when planted directly in the ground.

However, if your fig trees seem to be barely growing at all, fertilization might be necessary. As the saying goes, though, ‘if it ain’t broke, don’t fix it’.

If your trees seem healthy and they’re planted in the ground, there’s no need to add more nutrients in the soil. 

Now, if you’re growing fig trees in containers, it’s a different matter. Container-grown fig trees need much more care. Not only will you need to water the trees weekly, but you should also add fertilizer on a weekly basis. 

Cherry Trees

Similar to fig trees, most people find that they don’t really need to fertilize their cherry trees. The exception to this is if the soil they’re planted in isn’t nutritionally optimal, in which case, they might need a helping hand. 

If you aren’t able to test your soil for nutrients, the best thing to do is simply pay attention to the appearance and growth rates of your cherry trees. If they don’t look healthy or if they seem to be struggling to grow, some fertilizer might help. 

Assuming you’re growing your cherry trees in the ground outside, you may need to fertilize failing cherry trees every 2 to 3 months, but if you’re growing in containers, you’ll need to do this more frequently (around 4 to 6 weeks).

Peach Trees

Until your peach trees start producing fruit, you don’t need to worry about fertilizing peach trees. 

The only time you would need to fertilize peach trees before they get to the age where they should be bearing fruit would be if they were planted in poor soil. 

Typically, though, you should feed peach trees just twice per year, in March (pre-flowering) and then after the flowers appear.

Mango Trees

Mango trees are a little more high-maintenance than cherry, fig and peach trees for the most part. They need feeding three times per year.

The first fertilizer application should take place in spring, then again in summer, with a final feeding in the fall. 

If your mango trees are still young, though, just feed them twice in the middle of spring (around April) and in the middle of summer (between late June and early July).

They have similar feeding schedules to citrus trees, which is ideal if you grow both at the same time.

Container-Grown Trees

While container trees aren’t a species, growing your fruit trees in containers, either indoors or outdoors, will alter the frequency with which you should be fertilizing them. 

As you may have noticed from the fertilizing schedules we’ve outlined for different fruit tree species, container-grown trees often need to be fertilized more frequently than trees that are grown in the ground because they will get less natural nutrition from the soil. 

If you’re growing fruit trees in pots or containers, whether these are placed indoors or outdoors, you should be wary of using high-nitrogen fertilizers.

While nitrogen-rich fertilizer is usually great for in-ground fruit trees, too much nitrogen will overwhelm potted trees and might actually stop them from producing fruit, causing them to over-produce foliage instead.

So, for potted fruit trees, it’s generally best to choose a fertilizer with an NPK balance where the ‘N’ value is the lowest. 

The exception to this rule would be citrus trees, which always need more nitrogen regardless of whether they’re potted or not. The same is true for avocado trees.

Different Types Of Fertilizers

In addition to having different NPK balances (see FAQ section) and different application timings, individual fertilizers come in various forms.

There’s also an important distinction between organic fertilizer and synthetic formulas.

 Let’s get into the different types of fertilizers now, and when each one might be appropriate for your gardening projects. 

Organic & Synthetic

First of all, you need to know the difference between organic fertilizer and synthetic fertilizer. It might seem obvious that organic fertilizer is the better choice, but depending on your specific gardening needs, that might not always be the case. 

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A plant fertilizer can be considered organic if it’s made with plant-based materials and/or manure and natural material from animal sources. Conversely, inorganic or synthetic fertilizer contains man-made chemicals. 

Now, the benefit of synthetic fertilizer is that it can provide higher doses of nutrients. Therefore, if you have fruit trees in your garden that are ailing and in urgent need of some serious nutrition, synthetic fertilizer can be a good choice.

It also typically produces higher fruit yields compared to organic fertilizers. 

With that being said, there are equally good reasons to stick to organic fertilizers rather than formulas that contain synthetic chemicals.

Organic fertilizers are better for the environment and safer for wildlife, pets, and people since synthetic fertilizers can contaminate sources of water and poison animals that accidentally ingest them. 

Organic fertilizers are also slow-release most of the time, which means you don’t need to apply them as often and while they don’t deliver nutrients as quickly, they continue to do so for longer. 

Slow-Release Spikes

Now that we’ve covered the main differences between organic and synthetic fertilizers, let’s discuss the different forms in which you can purchase fertilizer for your fruit trees, starting with slow-release spikes. 

Fertilizer spikes release nutrients slowly, hence why they’re known as slow-release spikes. We love using fertilizer in this form because it’s so easy, particularly if you’re dealing with a lot of fruit trees. 

Spike fertilizer is measured out in the packaging already, so you don’t have to go through the process of meticulously measuring out the substance.

This takes both effort and worry out of the fertilization process since over-fertilizing your fruit trees can be damaging. 

Usually, you don’t even need to water at the time of fertilizing when you use spikes, so that’s another way in which this type of fertilizer makes gardening easier. 

Additionally, the way in which spikes are administered into the soil helps trees to build a resistance against pests and diseases that could damage or even kill them. 

Liquid Formulas

We don’t usually use or recommend liquid fertilizers ourselves for a couple of reasons, which we’ll get into in a moment, but since this kind of fertilizer is readily available, it’s worth being aware of the pros and cons. 

Liquid fertilizer doesn’t need to be administered with any water since it’s already in liquid form, so it’s often seen as an eco-friendly choice.

Liquid fertilizer delivers nutrients straight into the roots very quickly, so if you have unhealthy trees, liquid fertilizer could be the best option for you, especially if you know that the pH balance of your soil isn’t what it should be. 

With that being said, with liquid fertilizer, it can be difficult to tell if you’re applying it evenly around the root area since it doesn’t form a layer like granules or power (see below).

Plus, over-feeding is more of a risk with liquid fertilizer, and this can cause some real issues if you haven’t perfected the art of precise measuring and application. 

Fertilizer Granules

Fertilizer granules are a very common form of fertilizer, and for good reason. 

Granular fertilizer is typically slow-release, but it also usually has a high nutrient concentration.

This means that while it does release nutrients slowly, it still provides a lot of nutrition for your trees, meaning you don’t have to choose between low-maintenance fertilizing and immediate nutritional benefits. 

When you use granular fertilizer, you may be able to go as long as 9 months without having to re-apply your plant food.

You don’t need to water it, and since the granules are very often organic, contamination isn’t usually a concern. 

Application of fertilizer granules isn’t just infrequent – it’s also easy when you need to do it. All that’s required is a sprinkling of granules around the base, although you may need to use a rake to scratch it into the soil, especially if you want to avoid accidental consumption by wildlife. 

Fertilizer Powder

The final form of fertilizer we want to talk about today is fertilizer powder. This type of fertilizer, like most, has its advantages and drawbacks, so it’s worth weighing these up carefully before buying fertilizer in powder form. 

Powder fertilizer is really easy to apply because, like granules, you can simply sprinkle it around the roots of the tree in question. Alternatively, some manufacturers recommend mixing it with water to make a kind of fertilizer tea. 

If you’re on a budget, you might want to choose powdered fertilizer over other kinds because it’s generally more budget-friendly. 

However, the downside is that you need to measure the powder very exactly because overfeeding with such a concentrated type of fertilizer can cause root burn if you’re not careful. 

Frequently Asked Questions

What Does NPK Mean?

You will have noticed that we made a lot of references to NPK balances throughout our review section, but if you’re new to growing and fertilizing fruit trees, you might not know what this actually means. 

The letters ‘NPK’ stand for ‘Nitrogen, Phosphorus, and Potassium.

These nutrients are all essential for healthy fruit trees, but different ratios are more suitable for certain plants and trees than others, which is why you’ll find fertilizers with vastly different NPK balances. 

What Is The Ideal NPK Ratio For Fruit Trees?

Most of the time, fruit trees will need a fertilizer with a nitrogen-heavy NPK balance, which means that the first number will be higher than the other two. 

There are a few exceptions to this, though. Ultimately, the NPK ratio you choose for your fruit trees will depend on what fruit you’re growing and what your priorities are. 

For instance, if you want strong roots, you might want a 1-2-1 ratio, whereas if you want more flowers and fruits, a 2-1-2 ratio might be better. All-purpose fertilizers tend to have an even balance of nutrients. 

Bear in mind that the numbers you’ll see on fertilizer packaging won’t be ratios as shown above, but actually percentages.

For instance, if you see 5-3-2 on a fertilizer package, it means that it contains 5% Nitrogen, 3% Phosphorus and 2% Potassium. 

Can You Over-Fertilize A Fruit Tree?

Yes, it’s possible to over-fertilize or over-feed a fruit tree, and doing so can be detrimental to the health of your trees and your fruit yields. 

In fact, applying an excessive amount of fertilizer can kill a fruit tree altogether, especially if you don’t use a slow-release formula.

Excess nitrogen can cause root burn and damage the foliage, so it’s important to carefully follow the guidelines provided by the manufacturer of your chosen fertilizer. 

Final Thoughts

Thank you for taking the time to read this guide and ensure the continued growth and health of your fruit trees! We hope that you have taken something away from it and feel more confident in feeding your fruit trees. 

Remember that organic fertilizer isn’t always a better option than synthetic fertilizer. Both have benefits and drawbacks.

You should also pay close attention to the NPK balance of any fertilizer you’re thinking of buying. Depending on your fruit tree species, higher or lower nitrogen might be necessary. 

Finally, make sure not to underfeed or overfeed your fruit trees. Overfeeding can be just as damaging as under-nourishing your plants, so pay attention to the recommended doses and feeding schedules outlined by the product manufacturer.