Blueberries have soared in popularity in recent years, and for good reason given their ‘superfood’ status. Feeding them with the best blueberry fertilizers will make growing them a breeze, providing you get the watering and soil conditions right, too.
Blueberry bushes bring interest to the garden for most of the year, beginning in spring with delicate, white, bell-shaped flowers. Those blooms are followed up by lush green foliage that continues way beyond the heady days of summer, eventually turning red in fall. That’s not to mention the sweet-scented and irresistible blueberry fruit of late summer.
These are great shrubs for filling borders or growing in ornate containers on a patio or balcony. Whatever way you plan to grow your blueberries, this article will provide you with useful tips on how and when to feed these plants. I’ll also be revealing the best blueberry fertilizers currently on the market.
Top Blueberry Fertilizers
If you’re in a hurry, then I recommend you look no further than Down To Earth Acid Mix for all of your fruiting berries. However, if you just need to get the soil pH adjusted to hit that blueberry sweet spot, then grab yourself a bag of Jobe’s Soil Acidifier.
Best Berry Fertilizer
Down to Earth All Natural Acid Mix Fertilizer 4-3-6
Designed specifically to enhance soil conditions and provide the perfect balance of nutrients for blueberries when lowing soil pH is a priority.
Best Soil Acidifier
Jobe’s Organics Soil Acidifier 30%
Well worth having a high-quality soil amendment in your shed. Jobe’s 30% mix is perfect to give you more control over exact soil pH levels.
By the way, our site is supported by visitors like you. Some links on this page may be affiliate links which means if you choose to make a purchase, I may earn a small commission at no extra cost to you. Thanks for your support! You can find out more here.
Guide To Fertilizing Blueberries
Fertilizing blueberries in the right way will help you produce strong and healthy blueberry bushes year after year. Not only do they bring vibrant color and bushy foliage to your garden but they are also delicious to eat and are loaded with health-boosting antioxidants, essential nutrients, and minerals. Gardening that is great for our immune system health? Count me it!
Soil PH for Blueberry Plants
How often and when to use blueberry fertilizer depends very heavily on the pH level of your soil. So it’s crucial you check the pH levels in your soil with a soil test kit before you start planting.
Highly acidic soil, or soil with a pH level between 4.0 to 5.0, is unquestionably what blueberry plants need to thrive. These plants simply won’t grow in anything other than acidic soil. If your soil is alkaline and you have your heart set on growing blueberries, you’ll need to do one of two things to have a successful harvest.
You could choose to lower the pH level of the soil. This can be done by digging in sulfur chips, adding sphagnum peat to the base of the plant, or incorporating animal manure into the soil. This ‘top-up’ to acid levels will need to be done annually.
Alternatively, you can plant your blueberry plants in containers and buy acidic soil. In both instances, you’ll need to make sure you are fertilizing with an acidic fertilizer for blueberries.
I suggest testing the pH level of your soil with a soil testing kit both before you start growing and then annually thereafter in case you need to adjust the pH levels.
Choosing Fertilizer for Blueberries
Once you have brought your blueberry bush home and have planted it in the correctly adjusted soil, you should hold off fertilizing for at least four weeks.
If you have the right soil conditions, you may not have to use blueberry fertilizer very often, if at all. Indeed, once per year in early spring may suffice. It’s only if your blueberry plants are not producing foliage, flowers, and fruit that you should consider boosting the amount and frequency of fertilizer.
Too much fertilizer can cause the roots of blueberry plants to become sensitive to salt burn. This is a consequence of their natural habitat where they originally grew in forests of conifer trees in acidic soil. As a result, they require very few nutrients compared to other fruit-bearing trees and bushes.
If you do experience slow growth and a low harvest, then it’s time to provide extra nutrients to your blueberry plants. This can be done either with an organic or non-organic fertilizer.
Organic Fertilizer
Organic fertilizers offer a slow-release formula that delivers nutrients over a longer time period and is derived from animal or plant matter that has many nutritional advantages. They often contain a low concentration of nutrients, tend to decompose slower, and aren’t always ready to use.
Look for products with nitrogen sources such as blood meal or fish meal. Powdered seaweed and bone meal will provide all-important potassium and phosphorus.
Inorganic Fertilizer
Inorganic varieties of fertilizer typically get to work immediately. They usually smell less than organic fertilizer but they do contain synthetic ingredients.
Use products that include ammonium sulfate and potassium sulfate. These elements provide a good source of nitrogen and potassium.
Choosing an organic or inorganic formula comes down to personal preference based on product results and ecological opinion. Thankfully, there are many options available and also various ways of administering these products.
Fertilizer Spikes
Fertilizer spikes offer a slow-release solution that can last anywhere from one month to the entire growing season once they have been inserted into the soil.
Most fertilizer spikes that are available for feeding blueberry bushes are also suitable for other lime-hating plants and shrubs, such as Azalea, Camellia, and Rhododendron shrubs.
Powder And Granular Fertilizers
There is a great range of powders and granular fertilizers available that offer a no-nonsense, slow-release solution to your blueberry fertilizer needs.
They typically need to be administered by sprinkling around the base of the blueberry plant and then gently raking in. Most get to work quickly by releasing nutrients into the soil once dissolved by water or rainfall and, just like fertilizer spikes, they can last for weeks or months.
Granules and powders are a great option if you are gardening in acid soil and have a variety of acid-loving plants such as Azalea, Rhododendron, and Camellia as well as blueberry plants to feed.
Liquid Fertilizers
Liquid fertilizers need to be diluted in water before administering to blueberry shrubs and bushes. This form of fertilizer is fast-acting because it is absorbed by the blueberry plant’s root system from the first drop of moisture.
What I’m not keen on with liquid concentrates is how quickly they can be washed away either by heavy rainfall or over-watering. But they do provide a sudden surge of nutrients to any blueberry bush that’s in need of a little pick-me-up.
Feeding Blueberries N-P-K Ratio
Blueberry fertilizers typically contain nutrients that are specific to ericaceous (lime-hating) plants and are widely available.
It is fair to say that successful blueberry growing is more dependent on the type of nutrients contained within the fertilizer rather than the N-P-K ratio. For example, blueberry plants do not tolerate nitrate forms of nitrogen. Instead, their nitrogen source comes from nutrients such as urea, cottonseed meal, and ammonium sulfate. These are known as ammoniacal sources of nitrogen that naturally occur in acidic soils.
Acid Fertilizer
Many gardeners, myself included, need to rely on an acid fertilizer to give blueberry bushes the best chance of success. An acid fertilizer will help to lower soil pH to the acid-rich levels that blueberry plants need. Look out for fertilizers that contain ammoniacal nitrogen sources such as ammonia sulfate and sulfur-coated urea.
Ammonium Sulfate
Ammonium sulfate is widely used in blueberry growing because it can help to maintain as well as reduce the pH of soils. Ammonium sulfate causes an acidic reaction with soil and adds nitrogen and sulfur to the soil. Beware, though, if you are gardening in acidic soil because repeated use can reduce soil pH below the desired range of 4.0 to 5.0.
5 Fertilizers For Blueberries Reviewed
Whether you are lucky enough to have acidic soil that allows you to plant your blueberry bushes directly into the ground or you need to grow them in containers, I have all the insider knowledge and product facts to make choosing a blueberry fertilizer straightforward.
I’ve taken into account my own expert opinions as well as customer thoughts to provide a comprehensive review of blueberry fertilizer to ensure you have everything you need to know in order to produce a bumper crop of blueberries year after year.
pros
- 100% organic product and packaging
- An excellent all-round berry fertilizer, arguably the best
cons
- Can increase acid levels in soil so check pH levels regularly
If you need to lower the pH of your soil to get the right acid levels for blueberry growing, then this acid mix fertilizer from Down to Earth might be just what you are looking for. The added bonus with this fertilizer is you can use it for most other types of acid-loving plants, too.
It’s 100% natural with an N-P-K ratio of 4-3-6. This fertilizer contains feather meal and blood meal, plus 2.5% humic acids to boost the nutrient count and acidity of the soil. The packaging is even bio-degradable. So not only is it good for the environment but it will also ensure your plants get everything they need to produce large, healthy fruit in abundance. Check Down To Earth’s the latest price here on Amazon
How to use: Lightly rake the area around your blueberry plant. Sprinkle the required amount around the dripline and lightly dig in then water the area thoroughly. Repeat this in early and late spring and after harvest.
Customer reviews: This granular fertilizer won’t just look after your blueberries. It’s great for most other types of acid-loving plants, too. Users loved the versatility of this fertilizer and the company’s environmentally conscious approach. Suitable for all berries, grapes, and other acid-loving fruit crops.
pros
- Fast-acting fertilizer showing quick results
- Bio-Tone formula increases microbe population
- Suitable for use in all acid-loving plants
cons
- Mild smell as you would expect from an organic product
The second pick on my best blueberry fertilizers list is Espoma Organic Holly-Tone fertilizer. This is a fast-acting formula that is suitable for lots of acid-loving plants — not just blueberries.
Espoma branded products are unique because they contain their trademark Bio-tone microbes. This leads to better-conditioned soil and healthier plant growth that’s all achieved with 100% natural ingredients. Find Holly-Tone here on Amazon.
How to use: Use one cup of fertilizer for every 1ft of branch spread. If your blueberry shrub is three feet or larger, double the quantity. Sprinkle the required amount around the dripline and water thoroughly. Fertilize once in early spring and again in late spring for best results.
Customer Reviews: Holly Tone gets top marks from me and also received rave reviews from users. It gets to work straight away and results are visible within 2-3 weeks. I’ve seen struggling blueberry plants put out much healthier growth after just one application. I’ve also used it with great success as a Hydrangea fertilizer. Some reviewers found the smell a little unsavory but, hey, we are talking organic matter here and it’s a small sacrifice given the results.
pros
- Contains ingredients that help improve soil conditions in drought conditions
- Natural ingredients that make it kid and pet-friendly
cons
- Pets love the smell of it. Humans, not so much!
This organic variety of acid fertilizers from Dr. Earth is made from 100% natural ingredients and is a great way to improve the vitality and bloom potential of acid-loving plants. Not only does it contain the basic macronutrients in a ratio of 3-4-3 but it also contains a host of other beneficial trace elements.
For starters, it boasts the inclusion of soil microbes that help to provide nutrients to the root system of your blueberry bush in a more efficient way as well as helping you achieve a bigger and better crop of blueberries. It also contains Ecto and Endo Mycorrhizae. These are microscopic organisms found in soil that can be added to tree and shrub fertilizer to help nourish plants that may be susceptible to drought.
This blueberry fertilizer is suitable for use on many other acid-loving plants but, users beware, it stinks! If you can get past the smell — and, let’s face it, most of us can — for great results and a successful harvest, then this product will get to work straight away and will continue to provide nutrients for 3-4 months.
You can buy Dr Earth on Amazon.com here.
How to use: One reason for including this on my list is its ease of use. Simply sprinkle the required amount around your plants and then water them. I love that this product represents good value for money. I have loads of acid-loving plants in my garden and a little of this goes a long way, especially if you adhere to the manufacturer’s guidelines.
Customer reviews: This is an effective fertilizer for blueberries but is extremely smelly. Some users reported how attracted their cats and dogs were to the smell and advised that it needs to be watered in well to avoid pets digging it up.
Next up is another organic, this time from the premium manufacturer Espoma. Berry-tone Fruit and Berry Food is a slow-release formula that can be used year-round. It is suitable for feeding blueberries but can also be used as a fertilizer for strawberries, raspberries, and blackberries.
What you get with this granular product is Espoma’s exclusive Bio-Tone formula that provides a steady stream of nutrients to help your blueberry bushes produce healthy-looking foliage and luscious berries that are bursting with flavor.
I’m all about the value for money as well as the results you get from a product, and this blueberry fertilizer delivers on both fronts. I find that one cupful for each mature plant is all I need for outstanding results year after year. Check Espoma’s latest price here.
How to use: Following the manufacturer’s instructions, this fertilizer can be used in early spring and then once again after harvesting your blueberries. Sprinkle ¼ to ½ cup of granules around the dripline of your blueberry bushes, lightly rake into the soil, and water in.
Customer reviews: Users saw results and were impressed when using this product on both young and established plants. As you’d expect with organic fertilizer, this is a little on the smelly side.
pros
- Fast-acting and highly effective
- A well-known brand in the fertilizer market
cons
- Small packet for a premium price
What I love about this fertilizer from Miracle-Gro is it’s water-soluble, and that is good news for fertilizing blueberries, especially young plants. They simply don’t do well if they have been over-fertilized or if fertilizer ingredients such as sodium are allowed to build up in the soil around them.
Using this fertilizer for blueberries means you’ll quickly be rewarded with vigorous growth, luscious foliage, and a more voluminous crop. Find Micarcle-Gro here on Amazon.
How to use: This gentle formula dissolves quickly and evenly in water and can be used every couple of weeks. You’ll also be able to use it for all your other acid-loving plants. You just need to dilute the required quantity with water and then use a watering can to evenly distribute around the base of your plants. Do be careful to avoid the stems and foliage of blueberry plants as they can still be susceptible to burn.
Customer reviews: It performs well but is costly for how much you get.
pros
- Lowers soil pH to improve soil acidity
- Outstanding vibrantly-colored fruits and blooms
- Can use for many acid-loving plants
cons
- Highly attractive to cats and dogs
Finally, I want to recommend this organic fertilizer from Jobe’s. It works by using all-natural ingredients to decrease the soil’s alkalinity and can be used for lots of acid-loving plants including azaleas and hydrangeas, as well as blueberries.
I always advise clients to test their soil’s pH before applying the product. This fertilizer contains sulfur which is much-needed if you want to correct alkaline soil. Adding sulfur will help your plants produce vital proteins that are essential to an acid-loving plant’s development. Check prices here.
How to use: Pour the required amount of granules into the planting hole just before planting and reapply 2-3 times per year to maintain the correct pH level in the soil.
Customer Reviews: This product was awarded a 4.6/5 rating by 74% of customers who were impressed with the vibrancy of plants after use. Users said this was their ‘go-to’ when they needed to lower the pH level of alkaline soil. The only criticism was how attractive the smell of this product was to cats and dogs.
When To Fertilize Blueberries
To give your blueberry plants a head start, you will need to get fertilized at the beginning of spring just before the growing season starts. It’s important that the roots of blueberry plants have a chance to absorb nutrients before the leaves have fully formed.
For young blueberry plants or those that need a little encouragement and are lacking in growth, administer a further dose of fertilizer 6 to 8 weeks after the first application and toward the end of spring.
Mature blueberry bushes that are planted in acidic soil are unlikely to need any further fertilizing for the remainder of the growing season. However, container-grown plants or those grown in soil with a higher pH level can be fertilized for the remainder of the growing season but no more often than every two months.
A further dose of fertilizer should be administered after harvest as your blueberry plant moves out of the active growing season.
How To Fertilize Blueberries
It’s a good idea to loosen the soil around your blueberry plants before you start fertilizing. You can do this simply by giving the soil a gentle rake and being careful not to damage the roots.
Apply fertilizer carefully to the soil around the base of the blueberry plant. Be sure to avoid any contact with the stem, branches, and foliage as this can cause burning.
If you do accidentally get fertilizer in these areas, carefully brush it away. After fertilizing, rake gently again and give the area a watering.
Where a layer of mulch has been applied during the inactive season you will need to temporarily remove the mulch before applying fertilizer. In my opinion, mulching should always be generously applied on top of blueberry plant soil to add nutrients and suppress weeds.
Once the fertilizer has been administered, and you have watered it in, the mulch can be put back in place on top of the blueberry plant soil.
Final Thoughts on Fertilizing Blueberries
Bear in mind that choosing the right fertilizer for your blueberry bushes will depend on the pH level of the soil in your garden and also the maturity of your plants.
Best Berry Fertilizer
Down to Earth All Natural Acid Mix Fertilizer 4-3-6
Built to last this powerful string trimmer offers 80 min battery run-time. Bump feed head, with variable speeds.
Best Soil Acidifier
Jobe’s Organics Soil Acidifier 30%
Well worth having a high-quality soil amendment in your shed. Jobe’s 30% mix is perfect to give you more control over exact soil pH levels.
I really hope that this review helps you pick the right product for your needs. If you’re still unsure, consider the easy-to-apply and longer-lasting fertilizers that come in the form of no-nonsense Jobe’s Fertilizer Spikes or the Miracle-Gro Water-Soluble Plant Food. Or perhaps go for my top organic pick, Dr Earth’s Acid Fertilizer, which can be used for many other acid-loving plants in your garden, too.
