Hi, my sister bought a dogwood this past Spring to grow in her townhouse front yard. This tree is a native she picked at the Robinson Nature Center native plant sale. Now its leaves are covered by what looks like mold to me but we’re not sure. It’s also not thriving; it seems not to have grown much since planted. She waters it regularly to no avail. Your thoughts?
Your dogwood is severely infected with powdery mildew, a fungal disease. This disease has become more virulent in recent years. Fortunately, our native dogwood population has many resistant individuals, but others are not resistant and are weakened year after year. When seeds from dogwoods are planted, some will naturally be the ones that get this disease. This little guy is one of the non-resistant ones. Remove it. It will not improve.
There are good dogwood varieties on the market that will not get powdery mildew, such as flowering dogwood (Cornus florida) cultivars “Appalachian Joy,” “Appalachian Blush,” “Appalachian Snow” and “Appalachian Mist”.
You do not need to get one that is crossed with a Chinese dogwood in order to get good disease resistance. Buy the ones above.