Month-by-month lists of common plant diseases, pests, and other problems you may encounter in North Carolina yards and gardens.

Turfgrasses

Fairy ring (all turfgrasses)

Gray leaf spot (fescue/St. Augustinegrass)

Large patch (bermudagrass/zoysiagrass/centipedegrass/St. Augustinegrass)

Leaf spot caused by Bipolaris/Drechslera (bluegrasses/bermudagrass)

Red thread (Kentucky bluegrass/fescue/ryegrass)

Rust (Kentucky bluegrass/fescue/St. Augustinegrass/zoysiagrass)

Summer Patch (Kentucky bluegrass/fine fescue)

Woody Ornamentals

Multiple hosts: Phytophthora root rot, Armillaria root rot (sometimes producing mushrooms this time of year), conks of wood decay fungi such as Pseudoinonotus dryadeus (a.k.a. the weeping polypore), Botryosphaeria dieback, sooty mold, improper planting, overfertilization

Multiple shrub species: root-knot nematodes

Arborvitae: Phytophthora root rot, Armillaria root rot

Azalea: Phytophthora root rot, Armillaria root rot, Phomopsis dieback, stunt nematode, Azalea prominent caterpillars (Datana major; large caterpillars)

Boxwood: Phytophthora root rot, boxwood blight, boxwood stem canker (Colletotrichum theobromicola), nematodes (lesion, root-knot, spiral)

Cherry, flowering: shothole (Passalora) and leaf blight (Blumeriella) resulting in defoliation (at least shot-hole does … check on Blumeriella)

Cherry-laurel: shot-hole, Botryosphaeria canker/dieback

Dogwood, flowering: powdery mildew, scorch (heat/drought), Septoria leaf spot

English Ivy: anthracnose, bacterial leaf spot, Phytophthora root rot

Euonymus: powdery mildew

Hemlock: Rosellinia needle blight

Hydrangea: Cercospora leaf spot, Corynespora leaf spot

Indian hawthorn: Entomosporium leaf spot

Japanese black pine: pine wilt nematode

Japanese holly: black root rot, Armillaria root rot, Botryosphaeria canker/dieback

Junipers: Phytophthora root rot (except Eastern red cedar), Armillaria root rot

Leucothoë: powdery mildew – note red spots on top of infected leaves

Leyland cypress: Phytophthora root rot, Armillaria root rot, Cypress (Seiridium) canker, Botryosphaeria canker/dieback, Passalora needle blight, algae on foliage, internal browning

Loropetalum: bacterial gall (knot), Cercospora (Pseudocercospora) leaf spot

Magnolia, saucer: powdery mildew

Magnolia, Southern: algal leaf spot

Maple: anthracnose, Phyllosticta leaf spot

Oaks: bacterial leaf scorch, anthracnose (Discula, Apiognomonia), Tubakia leaf spot, secondary leaf spots, slime flux, Biscogniauxia canker, weeping polypore (Pseudoinonotus dryadeus)
*slime flux is mainly seen on oak but can occur on maple, elm, hickory, and some other hardwoods

Redbud: Cercospora (Passalora) leaf spot, bacterial leaf scorch

Red-tip photinia: Entomosporium leaf spot

Rose: Armillaria root rot, crown gall, black spot, Cercospora (Rosisphaerella) leaf spot, rose rosette

Spruce: Rhizosphaera needle cast

Sycamore: bacterial leaf scorch, anthracnose

Herbaceous Ornamentals (Perennials, Bedding Plants) 

Amsonia: rust

Aster: rust

Coreopsis: powdery mildew

Impatiens: Rhizoctonia crown/stem blight, downy mildew*
*New Guinea impatiens are not susceptible to downy mildew

Ironweed: powdery mildew, rust

Liriope: anthracnose on leaf tips, Fusarium crown rot

Peony: leaf blotch (measles)

Rudbeckia: Septoria leaf spot

Vernonia: rust

Vinca, annual (Catharanthus): Phytophthora root rot and aerial blight

Fruits & Nuts

Apple: bitter rot, sooty blotch and flyspeck, black rot

Blueberry: Phytophthora root rot

Grape, bunch: Pierce’s disease

Grape, muscadine: Pierce’s disease

Peach: brown rot (fruit phase)

Pear: Fabraea leaf spot

Vegetables & Herbs

Beans: anthracnose, Cercospora leaf spot, Rhizoctonia root/stem rot

Cole crops: Black rot, Rhizoctonia damping off

Cucurbits: downy mildew, powdery mildew, fruit rots

Arthropods of the General Landscape

Wheel bugs (adults)

Two-lined spittlebug (adults; often on hollies)

Arthropods Associated with Multiple Plants

Bagworms (Thyridopteryx ephemeraeformis; bags often containing eggs)