Dogwood trees are known for their beautiful spring blooms Their flowers come in white, pink, and red hues, lighting up the garden. However, you may notice the dogwood tree leaves turning red earlier than they should.
Red leaves on a dogwood are usually a sign of disease, pest infestation, or environmental stress While it may not kill the tree outright, it weakens the plant and ruins the ornamental value Acting fast is crucial to save your dogwood.
In this article, we will explore the three main reasons for red dogwood foliage and how to fix the problems.
Anthracnose Disease
The most common cause of red dogwood leaves is anthracnose, a fungal disease. It thrives in cool, wet weather and spreads easily through water.
You’ll first notice reddish or purple blotches forming on the leaf edges. Soon the leaves shrivel up and fall off the branches. Flowers and fruits may also get infected. Without treatment, the disease moves from the lower to upper branches, defoliating the entire tree.
How to Treat Anthracnose
Start treatment at the first sign of infection. Here are a few effective solutions:
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Remove and destroy affected leaves so the fungus doesn’t spread.
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Apply a copper-based fungicide like Bonide Copper Fungicide. Spray the product on early in spring before the leaves emerge.
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Try making a baking soda spray (4 tsp baking soda, 2 tsp oil, and 2 tsp liquid soap in 4 liters water). Spray onto the dogwood weekly.
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Improve air circulation and sunlight penetration by pruning dense growth. This discourages fungal growth.
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Water at the base, not overhead. Allow time for leaves to dry out during the day.
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Pick anthracnose-resistant dogwood varieties like Celestial, Ruth Ellen, and Stellar Pink. They are less prone to this disease.
Dogwood Borer Infestation
Dogwood borers are moth larvae that feed on the bark and inside the trunk. A severe infestation can kill young trees within a couple of seasons.
You’ll notice tiny holes in the bark with sawdust-like frass around them. The leaves start dropping as the borer damages the vascular tissues. Eventually the bark peels off as well.
Treating Borer Infestations
Catching borers early is key. Here are some remedies:
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Spray insecticide like Monterey Garden Insect Spray on the trunks to kill larvae. Follow label directions carefully.
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Make a homemade insecticidal soap with oil and soap. The solution suffocates the borers on contact.
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Apply neem oil or horticultural oil sprays. They deter borers from laying eggs on the bark.
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Remove and destroy severely infested branches before borers spread further.
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Avoid pruning during spring and summer when borers are active. Pruning wounds attract them.
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Clear weeds and mulch around trees. Borers hide in ground litter. Proper sanitation discourages them.
Dogwood Leaf Scorch
Leaf scorch causes red, browned leaves with distorted shapes. It happens when trees experience drought stress. Dogwoods have shallow roots and wilt easily.
While it doesn’t kill the tree, leaf scorch makes it vulnerable to deadlier diseases and pests. The foliage may cling on until fall or drop early.
Fixing Leaf Scorch Issues
You can revive moisture-starved trees through:
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Deep watering 2-3 times per week during drought and heat.
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Applying mulch to prevent evaporation and keep roots cool.
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Using a moisture meter to check soil dryness before watering.
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Pruning the canopy for better air flow inside the tree.
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Planting in part shade locations protected from hot afternoon sun.
When to Call an Arborist
Sometimes diseases or pests can’t be controlled at home. If more than 50% of the foliage is damaged or major limbs are dying off, call a professional arborist. They have specialized tools and treatments to diagnose and manage severe dogwood problems.
Catching issues early before widespread damage gives the best chance of saving ornamental dogwood trees. At the first signs of unusual red leaves, take prompt action. With proper care, your dogwood will keep blooming year after year.
Dogwood Anthracnose Dogwood anthracnose (Discula destructiva) symptoms on flowering dogwood.Photo: John Hartman, University of Kentucky, Bugwood.org
- Symptoms include dark spots on leaves and flower bracts, blighted leaves, and twig dieback. It lowers flowering and removes leaves (spring).
- Dogwood anthracnose is caused by a fungal pathogen, Discula destructiva.
- This used to be the worst disease for flowering dogwoods in our forests and on the ground, but it doesn’t happen as often now.
- Early signs show up as leaf spots with tan or purple edges in the middle to end of May. When it rains, these spots can get bigger quickly and kill the whole leaf.
- It starts on infected leaves and moves to twigs and branches, where it can kill off the limbs.
Dogwood Twig Borer Flagging of a branch caused by dogwood twig borer infestation. Photo: James Solomon, USDA Forest Service, Bugwood.org Dogwood twig borer larvae. Photo: Jim Baker, North Carolina State University, Bugwood.org
- The dogwood twig borer (Oberea tripunctata) eats the twigs and causes them to die and break off. This is a minor pest of dogwood.
- The adults beetles are 5/8 inch long with long antennae. Their wings are yellow and tan, and there is a black line down the middle and around the edges. There are two distinctive black dots just behind the head.
- In the spring, the adult beetle comes out of infested twigs, and the female lays her eggs in healthy twigs.
- The larvae (juveniles) are yellowish in color. They dig into the soft middle of twigs and may spew sawdust as they eat.
- Each year there is only one generation, and the larva stays inside the twig all winter.
- Infested twigs should be cut off a few inches below the part that is girdled or infested and thrown away. This needs to be done after the plant starts to wilt but before the adults come out in the spring.
Home Gardener – Tree Problems – Dog Wood
FAQ
Why do dogwood leaves turn red?
How do you treat leaf scorch on dogwood?
What are the signs of dogwood stress?
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Symptoms
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Details
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Frequency
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Leaves Browning
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Browning leaf edges, leaves drooping, wilting
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Occasional
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Early Fall Color (Summer)
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General stress. Peeling, cracked bark near the base of the tree, brown leaf edges/wilting purple/red leaf color
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Occasional
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Do dogwood leaves change color?
What’s wrong with my dogwood tree?
To find out what’s wrong with your dogwood tree, you’ll need to examine the leaves closely as telltale signs can help you to identify the source of your problem. Red and brown leaves are a sign of leaf scorch. Scorched leaves also tend to be dry and brittle around the edges.
Do dogwood trees turn red in the fall?
Dogwood Tree Leaves Turning Red. If you notice your dogwood tree leaves turning red in the fall, there is nothing to be worried about. Dogwood trees are known to turn red leaves during the fall season as a standard color change. However, something must be fixed if your tree turns red in summer.
Why is my dogwood tree turning yellow?
Yellowing leaves on dogwood trees are a likely sign of chlorosis. This occurs when the tree cannot take in sufficient amounts of iron to turn into chlorophyll — the stuff keeping the leaves lush and green! Things like overwatering can choke the roots and inhibit iron intake as can overly alkaline soil. Be sure to check your soil’s pH levels.