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The Best Fertilizer for Grapefruit Trees

If you’re looking for one of the healthiest fruit trees you can grow, a grapefruit tree should be at the top of your list. Grapefruit trees are a little tricky to grow, but the healthy and tasty benefits are well worth the work! Aside from ensuring that grapefruit trees are compatible with your climate, choosing the best fertilizer for grapefruit trees is the next most important thing.

Person spreading granular fertilizer, a popular form of fertilizer for grapefruit trees.

If you’re new to citrus trees and have no clue where to start, you’ve come to the right place. We’ve got five great grapefruit tree fertilizer options for you to choose from!

Our Top 5 Picks For Best Fertilizer For Grapefruit Trees

Best Overall Fertilizer for Grapefruit Trees

Earth Natural Wonder Fruit Tree Fertilizer

Look no further than Dr. Earth Natural Wonders Fruit Tree Fertilizer for the best fertilizer for grapefruit trees. Grapefruit trees are fussy, but they often require the same fertilizer and plant food as other citrus trees. Dr. Earth Natural Wonder is a good all-around option for any citrus trees you have, grapefruit included.

Dr. Earth fertilizers are 100% organic and made from natural ingredients, including seafood, fruit, and vegetable by-products. As such, they’re entirely safe for people and animals, making them a good choice if you have curious pets. This fertilizer comes in spike, granule, or liquid form, and also as a concentrate that you add water to.


  • Very easy to use and the best overall fertilizer for grapefruit trees
  • Pet and human safe
  • 100% organic without any GMOs, chemicals, or synthetic additives
  • The liquid concentration gets quickly into your tree’s root system


  • Slightly on the pricy end

Where to Buy

You can purchase this fine product at Nature Hills Nursery.

Runner-Up for Best Overall Fertilizer for Grapefruit Trees

Espoma Organic Citrus Tone

Espoma Organic Citrus-tone 5-2-6 Natural & Organic Fertilizer and Plant Food for all Citrus, Fruit, Nut & Avocado Trees; 8 lb. Bag. Promotes Vigorous Growth & Abundant Fruit

Espoma Organic Citrus Tone is arguably just as good as Dr. Earth Organic Fertilizer. Espoma Citrus Tone is 100% organic and naturally made from feather meal and humic acids and even contains live microbes that work their way into the soil for an extended lifespan. No matter what type of grapefruit trees or citrus trees you’re planting, Espoma Citrus Tone is the way to go.

The NPK ratio is 5-2-6, and this is one of the longest-lasting fertilizers on the market. In some cases, you only have to apply it every two years! It’s also known for producing bigger and better fruits than many other types of fertilizers.


  • Very long-lasting and requires few applications
  • Fairly affordable considering how good it is
  • 100% organic and natural
  • Includes a granulated formula designed for slow release


  • You won’t see instant results or even quick ones.

Where to Buy

You can purchase this fine product at Amazon.

Best Inorganic and Budget-Friendly Fertilizer for Grapefruit Trees

Miracle-Gro Shake and Feed Citrus Plant Fertilizer

If you’re not worried about organic versus inorganic and want to save a bit of money, Miracle-Gro is one of the top names in the fertilizer business. Their Shake and Feed Citrus Plant Fertilizer is no exception. It’s a product that’s easy to use and readily available at almost all plant and fertilizer stores and markets.

With an NKP ratio that’s 8-2-10, it’s an excellent option if you want to stimulate root and leaf growth while also increasing the amount of fruit per tree output. Granular fertilizers like this one take slightly longer to work their way into the soil than liquid fertilizers, but they’re ultimately just as effective. You simply shake the bottle, dump a few granules around the tree as directed, and work them into the soil.


  • Has added chemicals and synthetics that optimize plant growth
  • Fairly safe and easy to use and apply
  • The application lasts longer than many other inorganic fertilizers


  • It’s inorganic, which means it has added chemicals and synthetics.

Where to Buy

You can purchase this fertilizer by visiting Amazon.

Best Long Lasting Fertilizer for Grapefruit Trees

Jobe’s Organic Citrus Fruit and Fertilizer Spikes

Jobe's Organics 04226, Fertilizer Spikes, For Fruit & Citrus, 6 Spikes

If you’re looking for the best long-lasting fertilizer for grapefruit trees, it’s tough to beat Jobe’s Organic Citrus Fruit and Fertilizer Spikes. These spikes are durable and sink into your grapefruit trees’ root system over the course of several months. They’re easy to plant and even easier to manage.

These spikes have a ratio of 4-6-6, which makes them a well-balanced overall option. The best way to use these spikes is to install one every 12 or so inches around the perimeter of your tree. You should only have to install the spikes twice per season.


  • Very easy and low-maintenance to use
  • Longer-lasting effectiveness than granules or liquids
  • Only have to use it once every month-and-a-half or two months
  • Organic and natural ingredients


  • Improper use can lead to over-fertilizing your grapefruit trees.

Where to Buy

You can purchase these spikes on Amazon.

Most Robust Fertilizer for Grapefruit Trees

Jack’s Classic Feed

J R Peters Inc 52524 Jacks Classic No.1.5 20-10-20 Citrus Food Fertilizer

If you’re looking for the biggest bang for your buck in a fertilizer for grapefruit trees, look no further than Jack’s Classic Feed. It has an NPK formula of 20-10-20, giving it far and away the highest concentration of nitrogen, phosphorous, and potassium of any fertilizer on this list. In addition to the high load of NPK, this fertilizer is packed with several other key micronutrients.

Thanks to the high load of NPK, it’s possible to see results within the first week of application. Results should include greener, stronger, and more robust leaves and stems and increased fruit production.


  • Very high NPK formula for quick results
  • Very easy to apply
  • Results within a week of application
  • Comes in granule form, which means longer-lasting results


  • Not organic

Where to Buy

You can purchase this product by visiting Amazon’s website.

What to Look for in a Fertilizer for Grapefruit Trees

An Organic Option

When it comes to fertilizers and plants, organic is always better. Organic fertilizer means that all the ingredients in the fertilizer are 100% natural. It won’t contain chemical additives that may make the fertilizer more potent.

Inorganic fertilizers have been tailored and created to certain specifications. They contain additives that might make the fertilizer more potent in the short term but don’t last as long. Inorganic fertilizers are typically cheaper than organic ones.

A woman applying liquid fertilizer around a tree.

Contents of the Fertilizer

The three main ingredients in any type of citrus tree fertilizer are nitrogen, phosphorous, and potassium (NPK). The ratio of these ingredients is typically indicated on the side of your fertilizer with a 0-0-0 or 7-7-7 numbering style. The first number refers to nitrogen, the second to phosphorous, and the third to potassium.

Ideally, these numbers should be somewhere around 13-7-13, meaning that there are equal parts nitrogen and potassium and roughly half the amount of phosphorous. This could vary from grapefruit tree to grapefruit tree but should be something similar to 13-7-13.

Physical State of the Fertilizer

You can purchase your fertilizer in three different states: liquid, granular, and spike.

Liquid fertilizer gets into your grapefruit trees’ roots the fastest and is the easiest to absorb, but they aren’t as long-lasting.

Closeup of liquid fertilizer being used for houseplants.

Granular fertilizer is similar to taking a pill versus taking liquid medicine. It takes longer to get into the plant’s system but is just as effective as liquid fertilizer.

Closeup of person holding handfuls of granular fertilizer.

Using spikes is the best long-term solution. Spikes are exactly what they sound like – spikes made of fertilizer that you drive into the soil around your grapefruit tree. Over a series of weeks or months, the sustenance from these spikes gradually makes its way into your tree’s root system and fertilizes it.

Give Your Grapefruit Trees a Boost With a Fertilizer Treatment

When it comes to choosing the best fertilizer for grapefruit trees, it’s important to first get the pH level of your soil tested. From there, you can make the best and most informed decision about which fertilizer to choose. While any of the options on this list will enhance the productivity and health of your grapefruit tree, choosing the perfect one will maximize it.

Closeup of fertilizer granules around a tree.

Fertilizing is just one part of caring for your grapefruit tree. Want to learn more about grapefruits? Next, visit our grapefruit trees page to learn all about this big citrus: planting, growing, caring, cooking, and more!

Shopping for your garden can get overwhelming, fast. So if you’re looking for advice on tools and supplies, then you’re in the right place!