We have five different citrus trees (lemon, orange, tangerine, lime, and kaffir lime) along with one potted Meyer lemon, so we’ve done hours of research to find the right fertilizers.
This guide is designed for both planted and potted citrus trees, so by all means, stick around! I’m sure you’ll find this useful.
Why Do We Have to Use Fertilizer?
No matter if this is your first citrus tree or your 50th, you’re likely going to need to fertilize it and provide it with nutrients at some point.
This is especially true with potted citrus trees, as they have a limited amount of soil to work with. On the other hand, planted citrus trees can grow their roots to be far-reaching and access a wider area to absorb more nutrients from the soil. Because of this, if the soil is rich enough, planted citrus trees likely won’t need much fertilizer (if any at all).
However, the problem with many store-bought fertilizers is that they’re fast-release, meaning the potent nutrients can spread through the soil too quickly. This can either overload and kill the plant, or the majority of nutrients will be leached through the soil—unused by the plant.
Fortunately, there are a few brands out there that are not only slow-release fertilizer but organic and easy to use.
These Are the Top 2 Fertilizers for Citrus Trees
Why I Like Down to Earth the Best
While Jobe’s fertilizer spikes make it easy to fertilize your citrus trees, Down to Earth’s is a better fertilizer overall, especially for younger plants.
Down to Earth started in Oregon in the late 70s as a result of American gardeners demanding organic options to the countless synthetic fertilizers filling the shelves. They caught the market right on time to be a part of the booming organic movement in the 80s.
Today, most physical products outsource their manufacturing and production to other companies, which means standards are never as good and facilities are also shared with countless other products and brands.
On the other hand, Down to Earth owns their own manufacturing plant and carefully sources their suppliers to better provide a premium fertilizer with better ingredients. This not only benefits the tree but the microbes in the soil as well (which is even more important!).
Lastly, many of Down to Earth’s fertilizers are approved for growing organic crops that meet USDA’s organic standards. If this is important to you, you should be safe with their citrus mix. However, I would recommend double-checking the product description and their website to make sure it meets your standards, especially if you are growing commercially.
Down to Earth has an NPK (nitrogen, phosphorus, potassium) that’s better suited for citrus trees. Citrus are high nitrogen feeders and normally require double the nitrogen to phosphorus and potassium, so this means a ratio of 2:1:1.
So, looking at the NPK for each of these fertilizers, Jobe’s citrus spikes have an NPK of 3-5-5 (about half the nitrogen to phosphorus and potassium), while Down to Earth’s Citrus fertilizer has an NPK of 6-3-3.
Don’t get me wrong, Jobe’s fertilizer is great. The only difference is that the lower nitrogen content in their fertilizer will encourage fruiting and blossoming more than foliage growth, which is great for more mature citrus trees. But for most citrus trees, especially younger ones that still need some growing, Down to Earth’s NPK is a better choice.
While it’s not the main selling point, Down to Earth’s packaging is compostable, which is pretty cool since I like to look for any environmentally-friendly actions when I can, even if they’re small (bonus points if they’re easy to get on board with).
Even though it’s not the first thing I look for when shopping for a quality organic fertilizer, the little things do count.
What to Look for in a Fertilizer
Normally, when you are shopping for organic citrus fertilizers, there are a few key indicators that can help you spot what makes a good fertilizer vs a bad one. Here are some of the biggest differences to look for:
- Quality, organic materials
- Proper NPK
- Slow-release ingredients
- Transparent manufacturing
- How long the brand has been around (and its reputation)
As long as the fertilizer you find meets these factors well, it should be a safe bet to use for your plant. Remember, you can always start small with fertilizer to see how your citrus tree likes it.
If you notice any adverse or extreme reactions, like leaves falling off, then stop applying the fertilizer and try to determine the issue and if it came from the fertilizer. I wrote a whole post about what to do if your citrus leaves are falling off, so make sure to check it out.
If you’re not a fan of the two fertilizers I suggested above, and you want to do your own shopping, check out this page on Amazon for a good start.
What You Can Expect From Synthetic Fertilizers
Something that we often forget about is that just like how we do well with quality food and a healthy gut microbiome, plants do the same. Not only do they thrive on high-quality nutrients, but they also grow much better in soil that has a healthy microbe population.
Unfortunately, the majority of fertilizers made today are synthetic, which means they contain plastics and other chemicals. I don’t know what life forms out there that can eat plastic and still stay healthy, but it can’t be a good long-term solution.
This is also true for the microbes in the soil. Often, synthetic fertilizers are too potent and processed to be properly broken down by smaller life forms, like microorganisms.
So, while citrus trees can absorb and use some nutrients from synthetic fertilizers, it often comes to the detriment of the long-term health of the tree and the balance of the microorganisms in the soil.
How to Make Your Own Homemade Citrus Fertilizer
If you’re like me and you’re always experimenting or finding new ways to do something, or if you simply don’t want to buy fertilizer, you can make great citrus tree fertilizer at home. It’s also a great project to do with your family and friends.
I spent several hours researching and testing various methods for homemade citrus fertilizer and put it into a blog post, so make sure to check it out.