What Is Wrong With My Exacum?

Are the flowers covered with gray mold?

Are the plants stunted and die prematurely?

Are the roots dark brown, plants wilt, yellow, and die?

Are the leaves discolored, fine webbing may be present?

Likely cause for these symptoms is a fungal disease - Botrytis blight. Other symptoms include brown to black spots that may appear on leaves and petals. You can only prevent Botrytis blight disease by planting sweet alyssums in areas with good air circulation. Water plants sparsely. Infected plants should be removed. Spray weekly with a copper fungicide until the disease is under control.

These symptoms are most likely caused by fungal disease - Basal Rot. This disease attacks when soil temperatures are around 65 to 75°F. Discard any diseased plants to avoid infecting healthy ones. Maintain moderate temperatures. Avoid wounding plants.

These symptoms indicate a fungal disease - Pythium Root Rot. Remove and dispose of any affected plants. Do not overwater plants. Pot in the pasteurized soil mix. Apply a copper-based fungicide to protect plants.

Spider mites are known to cause problems for Exacum. Hose off plants when symptoms first appear. A strong stream knocks mites off plants and may give control. Introduce predatory mites. For severe infestations, spray plants with insecticidal soap or pyrethrin.

If the leaves are distorted and curled the culprits are aphids. These tiny insects cluster under leaves and on growing tips where they feed on plant sap. Leaves, stems, and buds get distorted, and later leaves and flowers drop from the plant. You can control them by washing them off the plant with water spray. Insecticidal soap should be used with severe infestations.