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Choosing the right fertilizer to maximize blueberry growth

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Choosing the best blueberry fertilizer

Blueberries grow best when planted in early spring. These superfoods are easy to maintain and are packed with antioxidants. You'll need the right mix of nutrients for a healthy blueberry bush with delicious fruits. Luckily, these berries don’t require much fertilizer, so you won’t need to buy a large bag.

If you're new to growing this fruit, consult our roundup of the best fertilizer for blueberries. We also answer a variety of common questions, such as when to fertilize blueberries and how to grow them in pots vs. your garden. 

Shop this article: Down to Earth All-Natural Acid Mix FertilizerEspoma Organic Holly-Tone Plant Food and Whitetail Institute Laboratory Soil Test Kit

Blueberry nutrient requirements

  • Phosphorus: When growing blueberry bushes, you’ll want a fertilizer with moderate phosphorous levels to support root development and fruit production. Using a fertilizer with the right amount of phosphorus ensures your berries’ roots are healthy, letting them absorb more water and nutrients from the soil.
  • Potassium: Blueberries require potassium-heavy fertilizers to aid in photosynthesis and overall plant health.
  • Be careful with nitrogen: Blueberries don’t process nitrogen like other plants. Avoid nitrate fertilizers and those high in nitrogen. You can use organic granular fertilizers that slowly release nitrogen or those containing urea. However, it’s important to note that urea is a synthetic compound.
  • Micronutrients: Blueberries require micronutrients including calcium, magnesium, sulfur and iron.

Soil pH

Blueberries grow best in relatively acidic soil. A soil pH between 4.2 and 5 is ideal for maximizing growth. You can use a pH testing kit or electronic pH tester if you’re unsure about your soil’s pH. If your soil is too alkaline, you’ll want to consider an acid-boosting fertilizer.

Organic fertilizer vs. chemical fertilizer

Organic fertilizers, such as compost and manure, are becoming increasingly popular for blueberry growing. These fertilizers release nutrients slowly and can improve the health of your soil. These are ideal for providing nitrogen slowly, so you won’t have to worry about the fertilizer damaging your roots. Still, some may not offer the immediate boost of potassium your plants need.

Chemical fertilizers generally have a more controlled concentration of nutrients, making them ideal for those looking to fine-tune their blueberries’ growth. However, these release nutrients quickly and can burn up your plant’s roots if they have too much nitrogen.

Blueberry fertilizer FAQ

When should you fertilize blueberries?

The best time for fertilizing blueberries is early spring. These plants grow best when you use small amounts of fertilizer in one to three applications depending on their size and age. Fertilize your bushes before their leaves are fully developed and again six weeks later. Some gardeners recommend fertilizing once more after your first harvest.

Can you grow blueberries in a pot?

If your garden soil conditions are not optimal, growing blueberries in pots is a great solution. The pots should have a minimum 12-inch diameter for young plants and around 18 to 20 inches for more mature plants. Deep and wide barrel planters are great if you want to grow blueberries long-term. 

How much sunlight do blueberries need?

Around six to eight hours daily. They tolerate some shade but don't need it unless it's particularly hot outside.  Additionally, proper sunlight and watering habits will reduce their need for fertilizer.

How often should you water your blueberries?

Blueberries need around 1 inch of water weekly. If you live in a particularly rainy area, you won't need to water your plants as often. Keep an eye on your area's weekly rainfall and avoid root rot by not overwatering your plants.

How do you know if your blueberries aren't getting enough fertilizer?

Underfertilized blueberry bushes tend to have small leaves and reduced growth. If you're worried about your soil's nutrient content, there are affordable nutrient test kits.

Best blueberry fertilizers

Down to Earth All-Natural Acid Mix Fertilizer

This all-natural fertilizer is an excellent way to boost your soil's acidity. The box is compostable and recyclable. Many reviewers said it helped revive their dying blueberry bushes.

Espoma Organic Holly-Tone Plant Food

This organic fertilizer releases nutrients slowly, ensuring they won't damage your blueberries' roots. It's an ideal solution for acid-loving plants, such as blueberries.

Espoma Organic Soil Acidifier

This helps create the ideal pH level for blueberries. It comes with more than enough for several blueberry bushes.

Espoma Organic Berry-Tone

This gives your blueberries a small instant dose of nutrients, followed by a slow release of nutrients over time. It contains bone meal, alfalfa meal and other natural ingredients.

Other products to help you grow blueberries

Sonkir Soil pH Meter

This doesn't require batteries and provides fast, accurate results. It is user-friendly and can be used for indoor or outdoor gardening. It tests your plants' lighting conditions, as well as the soil pH and moisture.

Whitetail Institute Laboratory Soil Test Kit

With this kit, you'll collect a soil sample and send it to a lab for testing. It provides accurate results about your soil's pH and available nutrients. It's surprisingly affordable.

Atree Soil pH Meter

This affordable meter is battery-free and easy to use. It can be used for an indoor or outdoor garden.

FiveJoy Garden Tool Set

This gardening tool set comes with two trowels, a weeder, a cultivator, a hand rake, pruning shears, gardening rope, a handheld sprayer, gloves, pruning snips and a cloth tote. The tools are rust-resistant and the gloves are durable.

KI Store Garden Kneeling Pad

This kneeling pad is made with extra-thick memory foam to keep your knees from getting sore while you tend to your blueberry bushes. It resists moisture and folds in half. The handles make it easy to pack around.

Picnic at Ascot Garden Tools With Tote

This is made of a durable canvas that's ideal for outdoor use. It has pockets to keep your tools separated. The solid base prevents it from sagging when you carry it.

Prices listed reflect time and date of publication and are subject to change.

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