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Which fertilizer for blueberries is best?

It’s no wonder many home gardeners love growing blueberry plants. Not only are the berries delicious, but the plants are also relatively simple to grow in a garden or container. However, if the soil doesn’t have the necessary nutrients or the proper pH balance, blueberry plants may not produce the beloved fruit. That’s where fertilizer that’s formulated especially for blueberries comes in.

Acidic soil that contains important nutrients like iron and nitrogen is ideal for blueberry plants. A fertilizer like MicroLife Acidifier elevates soil’s acidity, adds nutrients and is made with natural organic ingredients to give blueberry plants the boost they need to grow strong and produce flavorful berries. 

What to know before you buy fertilizer for blueberries

Before you grab a garden hoe and begin working with the soil in preparation to cultivate blueberries, it’s important to understand soil contents and the role fertilizer will play in the success of your plants. 

What is soil pH?

When it comes to soil, pH is the measurement of alkaline or acidity. A pH rating between 6.5 and 7.5 is considered neutral, while a value higher than 7.5 is alkaline. Soil that measures 6.5 or less on the pH scale is considered acidic, with 4.3 to 5.5 pH being ideal for blueberries. 

What nutrients do blueberries need?

Just like other plants, blueberries need a variety of soil nutrients for strong growth. Nitrogen, iron, magnesium, sulfur and phosphorus are key for plant development. 

How to fertilize blueberry plants

The best time to fertilize blueberries is in the spring to prepare them for the growing season ahead. Following up in about six weeks with a second application should suffice for the year, although some fertilizer manufacturers recommend application in the fall for winter nourishment. Watering plants before and after applying fertilizer will distribute the nutrients deep into the soil. 

As a general rule, always follow the instructions on the fertilizer package for the best results. Also, keep in mind that you should never over-fertilize plants, as too much can throw off the balance of soil nutrients and slow down growth. 

What to look for in quality fertilizer for blueberries

Types of fertilizer for blueberries

Fertilizer for blueberries is typically available in two forms: powdered, which must be mixed with water and applied in liquid form; and granular or pelletized, which is made to be sprinkled around plants. 

Some fertilizers state that they offer blueberry-appropriate formulas on the label. However, others may be referred to as acidifiers, and include a list of plants they are suitable for on the packaging. In addition to blueberries, this will include other acid-loving plants like azaleas, rhododendrons, hydrangeas and camellias. 

NPK rating

NPK stands for the ratio of nitrogen, phosphorus and potassium in fertilizer. An example is 1-1-1, which simply means that a fertilizer with this rating contains 1% of each of these three macronutrients. Fertilizers that are suitable for blueberries will have a higher ratio of these nutrients for optimal growth. For example, NPK ratings of 6-2-4 and 4-3-6 are examples of ideal nutrient combinations for blueberries. 

Organic vs synthetic fertilizer

If you’ve ever shopped for fertilizer for other types of plants, you might have noticed that most varieties come in synthetic or organic forms. However, because blueberries thrive in acidic conditions, the best fertilizers for them are organic and chemical-free. These formulas typically contain helpful microbes, potash, fishbone or kelp meal that help produce high levels of nitrogen, resulting in lower pH values. What’s more, they are safe for blueberry plants’ delicate root systems. 

How much you can expect to spend on fertilizer for blueberries

Fertilizer for blueberries range in price from about $12 for enough for several plants to as much as $100 for a crop of blueberry bushes. 

Fertilizer for blueberries FAQ

What are some obvious signs my blueberry plants need fertilizer?

A. The slow growth of blueberry plants is a common effect of deficient soil, but it can take a while to notice. However, discolored leaves is a clear sign that you need to intervene with a quality fertilizer. In other words, if your plant’s leaves aren’t rich green in color, there’s a problem. 

Should I test the soil before using fertilizer for blueberries?

A. Absolutely. Because understanding the soil’s acidity level is crucial, make sure the test you choose measures pH values. 

What’s the best fertilizer for blueberries to buy?

Top fertilizer for blueberries 

MicroLife Acidifier Biological Fertilizer

MicroLife Acidifier Biological Fertilizer

What you need to know: A natural, organic fertilizer that enhances soil’s acidity and produces excellent results. 

What you’ll love: Along with being organic, this acidifying fertilizer is packed with nutrients and quality micro-organisms that help plants thrive. The easy-to-use granular form comes in a convenient canister. 

What you should consider: The manufacturer recommends applying the product every three to four months, which is more frequent than some similar products. 

Where to buy: Sold by Amazon

Top fertilizer for blueberries for the money

Down to Earth All Natural Fertilizing Acid Mix

Down to Earth All Natural Fertilizing Acid Mix

What you need to know: An excellent choice for improving soil’s acid levels thanks to the 4-3-6 NPK rating and natural formula. 

What you’ll love: This fertilizer is made especially for blueberries, as it gives soil the necessary acid boost for superior growth. It’s all-natural and comes in a compostable box.

What you should consider: For the best results, you must mix this fertilizer with the appropriate amount of water indicated on the packaging. 

Where to buy: Sold by Amazon

Worth checking out

Espoma Organic Soil Acidifier Fertilizer

Espoma Organic Soil Acidifier Fertilizer

What you need to know: This is another quality acidifying fertilizer that is formulated to improve the growth and production of blueberry plants. 

What you’ll love: Made from organic ingredients, this product lowers the pH levels in soil naturally and safely. In addition to blueberries, it’s also great for hydrangeas and other acid-loving flowering plants. 

What you should consider: Some customers report that it takes a while to see noticeable results after use. 

Where to buy: Sold by Home Depot and Amazon


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Jennifer Manfrin writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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