Blueberry Leaves Turning Brown

Seeing your blueberry leaves turning brown is a clear sign of plant distress. It’s a common issue that can have several causes, but don’t worry—it’s often fixable with the right approach. This guide will help you figure out why it’s happening and what you can do about it.

Brown leaves on blueberries are your plant’s way of telling you something is wrong. It could be a simple watering issue, a lack of nutrients, or something more serious like a disease. The key is to look at the pattern of browning and other clues to diagnose the problem correctly.

Before you take action, you need to play detective. Look closely at your plant. Are the brown spots on the edges or in the middle of the leaf? Is the whole leaf brown or just parts? Are new leaves affected, or only old ones? The answers will point you in the right direction.

Common Causes and How to Fix Them

Let’s break down the most likely reasons for browning leaves, from the simplest to the more complex.

1. Water Stress (Too Much or Too Little)

Blueberries have shallow, fine roots that are sensitive to water. Getting the balance wrong is a top cause of brown leaves.

Underwatering: Leaves will often turn brown and crispy, starting at the edges and tips. The plant may also wilt. Blueberries need consistent moisture, especially when fruit is developing and during dry spells.
Overwatering: This leads to soggy roots that can’t breathe. Leaves may turn a dull brown or yellow before browning and dropping. It’s a common problem in heavy clay soils or pots without good drainage.

The Fix: Check soil moisture regularly. Stick your finger about 2 inches into the soil. It should feel damp, not sopping wet or bone dry. A deep watering once or twice a week is usually better than frequent light sprinkles. Adding a layer of pine bark or pine needle mulch helps retain even moisture.

2. Soil pH Problems

This is critical. Blueberries are acid-loving plants. They thrive in soil with a pH between 4.5 and 5.5. If your soil pH is too high (alkaline), the plant can’t absorb nutrients properly, leading to a condition called chlorosis and eventual browning.

Signs: Leaves often turn yellow between the veins first (interveinal chlorosis), then the edges and tips may turn brown and crispy.

The Fix: Test your soil pH. You can buy a simple kit from a garden center. If the pH is too high, you can lower it by applying elemental sulfur or a fertilizer for acid-loving plants. This process is slow, so be patient. Amend the soil in late fall or early spring.

3. Nutrient Deficiencies

Even with the right pH, blueberries can lack specific nutrients, causing browning.

Potassium (K) Deficiency: Causes scorched brown edges and tips on older leaves first.
Magnesium (Mg) Deficiency: Shows as yellowing between leaf veins on older growth, with edges that may turn brown and curl upward.

The Fix: Use a balanced, slow-release fertilizer formulated for acid-loving plants (like azalea/camellia food) in early spring. For a quick magnesium boost, you can dissolve 1 tablespoon of Epsom salts in a gallon of water and apply it to the soil. Avoid over-fertilizing, as this can burn roots and make problems worse.

4. Fungal Diseases

Several fungal issues can cause brown spots or patches on leaves.

Leaf Spot Diseases (like Septoria or Gloeosporium): You’ll see small, circular brown or gray spots on leaves, which may eventually cause the whole leaf to yellow and drop.
Leaf Rust: Appears as yellow-orange pustules on the undersides of leaves, with corresponding yellow or brown spots on top.
Botrytis Blight: Often causes a gray mold and browning, especially in cool, wet conditions.

The Fix:

Clean up! Remove and destroy all fallen, diseased leaves in autumn.
Improve air circulation by pruning your bushes so light and air can get inside.
Water at the base of the plant, not overhead, to keep leaves dry.
If needed, apply an organic fungicide like neem oil or a copper-based spray as a preventative in early season, following label instructions carefully.

5. Winter Damage or Salt Injury

If browning appears in early spring, consider environmental factors.

Winter Burn: Cold, dry winds and winter sun can desiccate leaves, causing them to turn brown. This is especially true for young plants or less hardy varieties.
Road Salt: If you live near a road, spray from de-icing salts can damage foliage, causing browning on the side facing the road.

The Fix: For winter protection, you can use a burlap screen to shield plants from prevailing winds. For salt injury, flush the soil around the plant with plenty of fresh water in early spring as the ground thaws to help leach salts away.

Your Step-by-Step Diagnostic Checklist

Check the soil moisture. Is it too wet or too dry? Adjust your watering habits accordingly.
Test the soil pH. This is a non-negotiable step for blueberry care. You can’t guess the pH accurately.
Examine the pattern of browning. Edges and tips? Spots? Yellowing first? Match it to the symptoms above.
Look at the overall plant and its location. Is it crowded? Are leaves wet often? Is it exposed to wind or salt spray?
Review your fertilizing history. Have you fed it recently? With what? Could it be a deficiency or burn from over-fertilizing?

By working through this list, you’ll likely identify the culprit. Remember, sometimes more than one issue is at play, like a plant in poor soil also getting a fungal disease because it’s stressed.

Prevention is the Best Medicine

Keeping your blueberries healthy from the start is easier than fixing problems. Here’s how to prevent those brown leaves:

Plant them right: Choose a sunny spot with well-draining, acidic soil. Amend the planting hole with plenty of peat moss or composted pine bark.
Mulch annually: A 3-4 inch layer of pine needles, pine bark, or oak leaves helps maintain soil acidity, moisture, and temperature.
Prune correctly: Prune in late winter to remove dead wood and open up the center for air flow. This reduces disease risk.
Water consistently: Set up a drip irrigation system or soaker hose to provide deep, even watering without wetting the leaves.

FAQ: Blueberry Leaf Problems

Q: Why are my blueberry leaves turning brown and falling off?
A: This is a classic sign of distress. It can be due to normal seasonal dieback of old leaves in fall, but if it’s happening in spring or summer, it’s likely caused by over/underwatering, a fungal leaf spot disease, or sever pH imbalance.

Q: What causes brown edges on blueberry leaves?
A: Brown, crispy edges are most often caused by underwatering, low humidity, or a potassium deficiency. Wind scorch can also cause this symptom.

Q: Should I cut off brown leaves on my blueberry bush?
A: You can gently pluck off severely brown and dead leaves to improve appearance and reduce hiding places for pests. However, avoid excessive pruning during the growing season. Focus on removing them during your main dormant season prune.

Q: Can a blueberry bush recover from brown leaves?
A> Yes, absolutely. Once you correct the underlying issue—whether it’s watering, pH, or a nutrient problem—the plant will put out new, healthy growth. Leaves that are already brown won’t turn green again, but they will eventually be replaced.

Q: Is it normal for blueberry leaves to turn red or brown in autumn?
A: Yes! Many blueberry varieties have beautiful fall color, turning vibrant shades of red, orange, and purple before they drop. This is a normal and healthy seasonal change, not a sign of distress.

Figuring out why your blueberry leaves are turning brown takes a little observation, but it’s a solvable problem. Start with the basics: check your watering habits and test your soil pH. Those two steps alone will solve a majority of cases. With consistent care and the right acidic conditions, your blueberry bushes can bounce back and provide you with healthy foliage and a great harvest for years to come.