Understanding Black Spot on Kelsey's Dogwood and Effective Prevention Tips
What is the problem?
Black Spot on Kelsey's Dogwood
Recently, a customer reached out with concerns about a few Cornus kelseyi (Kelsey's dogwood) plants they had just received from us. They noticed black spots on the leaves and wanted to ensure the plants were healthy. Their concern is entirely understandable—spotting disease on new plants can be alarming!
However, in this case, we were happy to assure them that what they saw was not a significant issue but a common occurrence in nursery settings, especially during the fall.
What Causes Black Spot on Cornus kelseyi?
Dark, circular spots on the leaves of affected plants characterize it. It is most commonly caused by high humidity and poor air circulation, which allow fungal spores to develop on wet leaf surfaces. While black spot can affect a plant's aesthetic appearance, it rarely leads to serious health issues if adequately managed.
Cornus kelseyi, like many dogwoods, can be susceptible to black spot, especially during the growing season when humidity is high. In most cases, this is not a sign of poor plant health but a temporary condition that comes with the territory in a nursery setting. When plants are grown closely together in containers, moisture can sit on the leaves for extended periods, creating the perfect environment for the fungal spores to take hold.
Why It's No Long-Term Concern
With fall in full swing, many plants, including Cornus kelseyi, are naturally preparing to go dormant. Leaves will drop soon, and any signs of black spot will disappear along with them. Once spring rolls around, the plant will produce fresh, healthy leaves.
In short, this issue is mainly cosmetic at this stage and has no lasting impact on the plant's health.
What Can You Do to Help Your Cornus kelseyi Thrive?
While black spot may not cause long-term harm, there are a few simple steps you can take to minimize the risk of fungal issues and promote a healthy plant next year:
Fall Leaf Removal: In the fall, removing fallen leaves from around the plant's base is a key step. Black spot spores can linger in leaf debris, so cleaning up can help reduce the chance of reinfection next year.
Consistent Watering: Ensure the plant gets consistent water throughout the growing season. Avoid letting the soil dry out completely, and ensure good drainage to avoid waterlogged roots.
Why Cultural Practices and Conditions Matter
It's important to remember that cultural practices—such as spacing, irrigation, and air circulation—can vary between nurseries, so the prevalence of black spot can differ from one season to the next. In any nursery, conditions may favor the temporary appearance of fungal diseases like black spot, but these issues typically resolve once the plants are in a well-maintained garden environment. To help ensure success, provide ample spacing and good air circulation in your garden.
The Takeaway
If you see black spots on your Cornus kelseyi this fall, don't worry— leaf clean-up and proper watering in the next growing season will ensure your plant thrives. You could apply a general fungicide in the spring to minimize the risk if you want extra precaution.
Our goal is always to provide you with healthy, high-quality plants, and we're here to support you every step of the way, whether addressing concerns or offering care tips for your garden.