Sawflies resemble caterpillars but it is important to distinguish between the two in order to select the proper insecticide labeled for sawflies. Sawflies generally have more than 6 prolegs (enough to spell SAWFLY on their abdomen without tiny hooks at the end of the proleg. Caterpillars are often larger in size than sawflies with five or fewer fleshy prolegs that have with tiny hooks at their end.
See photos and descriptions: Butterfly and Moth Larvae vs Sawfly Larvae
Begin the mum season by reviewing your fertilizer program and teaching new employees to recognize symptoms of Chrysanthemum white rust.
Plants in retail yards may be showing signs of nutrient deficiency as well as botrytis blight and possibly root rots.
Clean plants by shaking hanging baskets over a trash barrel to dislodge spent flowers. It is also a good time to check the root health of plants. Healthy roots will be firm and fill out the pot. Decaying flowers and plants give off ethylene which will contribute to premature loss of foliage and flowers or premature flower death of nearby plants, so removed dead and decaying plant material. Plants sensitive to ethylene include geraniums, salvia and snapdragons.
A reminder that Zonal and seed geraniums, American marigold, and all types of impatiens are susceptible to iron/manganese toxicity, a nutritional disorder associated with low growing medium pH. This problem is sometimes called "bronze speckle" due to the appearance of numerous small brown spots on the edges of the leaves of geranium and marigold. The target pH range to prevent toxicity is 5.8-6.5. If the pH is lower than the target range the risk for toxicity increases because at low pH too much iron and manganese becomes available to the plants.
Downy mildew of Coleus, Peronospora lamii, was first detected in New York and Louisiana in 2005; by 2006 it was present throughout the United States. Downy mildew is closely related to Phytophthora and Pythium. Symptoms include brown, irregular lesions on leaves and leaf drop. Because the lesions are irregular, infection can cause the leaves to twist and distort before dropping. In cool, wet, humid conditions sporangia may be visible as a downy gray to purplish growth on leaf undersides.