Aphids live and feed on the underside of lilac leaves, causing them to curl or producing small holes in the leaves. If necessary, transplant the bushes to a sunnier area or farther apart for increased light and airflow. Powdery mildew will rarely cause a lilac bush to die but causes significant surface damage and defoliation. Kristi Waterworth started her writing career in 1995 as a journalist for a local newspaper. Shoemaker Richards also edits for several independent literary journals and the Pink Fish Press publishing company. Protecting the lilac is key to keeping its leaves healthy. They were fine last year. Powdery mildews are a group of host-specific fungi whose subspecies often trouble gardeners when other fungi are inactive. Samantha Volz has been involved in journalistic and informative writing for over eight years. High heat and humidity, overwatering, lack of sunlight and closely spaced plants all lead to the development and spread of powdery mildew among lilacs. Additionally, fungal diseases such as powdery mildew cause leaves to curl as the leaves are wounded and the plant starts to die. Curling leaves are an early symptom followed by white, mold-like growth covering the leaves and flowers. From there, her meandering career path led to a 9 1/2 year stint in the real estate industry. Additionally, fungal diseases such as powdery mildew cause leaves to curl as the leaves are wounded and the plant starts to die. The same organism is the source of bacterial blight on pear, blueberry, cherry, maple, and many other woody plants and the symptoms of lilac blight are similar in appearance to fire blight in fruit trees. Severe infestations cause the entire lilac bush to exhibit curled leaves. Several problems can cause lilac leaves to curl. If the leaves of your lilac are curling or distorting, you may be facing either a disease or an insect infestation. Lilac leaves turn brown at the edges from lack of water. Removing nearby plants and thinning the interior of a lilac will allow more air movement inside the canopy, causing the fungus to desiccate. Treat aphids with horticultural oils or pesticides. Powdery mildew will rarely cause a lilac bush to die but causes significant surface … Removing severely damaged branches helps slow the spread of the disease and encourages new lilac growth to emerge, which helps restore the plant's health. Although leafminer damage is primarily a cosmetic problem, it does make the lilac more susceptible to other pest and disease problems. Severe infestations cause the entire lilac bush to exhibit curled leaves. Apply fungicides to lilacs that have curled leaves; fungal diseases such as powdery mildew spread until they cover the entire plant and sometimes lead to the death of the lilac. Actually known to plant pathologists by the complete name of "lilac bacterial blight," this disease is caused by a bacterium Pseudomonas syringae pv. The leafminer, a small insect that tunnels inside leaves, causes the leaf to curl up around it as it weakens the structure of the leaf. USA National Phenology Network: Planting and care for lilac. Mix organic soil amendments, such as compost or manure, into the surrounding soil to improve drainage. Lilacs (Syringa spp.) Other natural predators include spiders, beetles and ladybugs. These long-adored bushes are usually easy keepers with few troubles, but chronically bothered by powdery mildews that can cause leaf curl. 2008, North Dakota State University; Questions on Lilacs; Ron Smith. If necessary, transplant the bushes to a sunnier area or farther apart for increased light and airflow. She resides in Horsham, Pennsylvania. In college she was editor-in-chief of the student newspaper and completed a professional internship with the "Williamsport Sun-Gazette," serving as a full-time reporter. Could you tell me why they are doing this. bring a distinct fragrance that with one distant whiff can evoke images of the multi-stemmed, purple-flowered bushes throughout U.S. Department of Agriculture plant hardiness zones 2 through 8, depending on cultivar. Some birds will feed on aphids. Temperatures between 60 and 80 degrees Fahrenheit, overcrowded plantings and shaded locations create the ideal growing environment for most powdery mildews, which can germinate even in dry conditions. Fungicides formulated to control powdery mildew help kill the fungal spores and stop the spread of the disease. She holds a bachelor's degree in English literature from Lycoming College, Williamsport, Pennsylvania, with a minor in European history. If your lilacs are in need of chemical rescue, several safer and effective products are available for powdery mildew control. Cut back areas where branches rub together. Additionally, fungal diseases such as powdery mildew cause leaves to curl as the leaves are wounded and the plant starts to die. You can also attempt to move the lilac to a sunnier, more open location once it goes dormant, but this can be a difficult task if the plant is large. University of Rhode Island; Powdery Mildew on Shrubs, Purdue University Extension; Leaf Diseases; Janna Beckerman; Mar. Powdery mildew. Copyright 2020 Leaf Group Ltd. / Leaf Group Media, All Rights Reserved. Spray the plants on an overcast but dry day, following package directions for proper application. Like powdery mildew, an aphid infestation rarely kills the plant but causes the leaves to curl, die and fall. Some fungicides; including chlorothalonil, copper and sulfur; help combat powdery mildew. Syringae. What Are the Treatments for Black Spots on Pear Tree Leaves? Applying pesticides to control leafminers is important for protecting the leaves of the lilac bush. The bacteria Bacillus subtilis can prevent re-infestation by powdery mildew if applied before the disease takes hold. Powdery mildew is often controlled using simple cultural modifications aimed at increasing the circulation around a troubled lilac. Since 2010, she's written on a wide range of personal finance topics. Eventually, the leaves turn brown and black and fall off the bush. Applying pesticides to control leafminers is important for protecting the leaves of the lilac bush. Symptoms on Lilac. It is also important to apply dormant horticultural oils in the early spring to kill any remaining eggs from the previous season and prevent further infestations from occurring.