See details below the chart.

Solving Balloon Flower Problems
Symptom	Probable Cause
Plant rots; Die over Winter	Crown Rot
Ragged holes in Leaves	Slugs and snails
Leaves Mottled; Blotched	Botrytis Gray Mold
Powdery Spots On Leaves; Yellowing	Rust
Leaves Covered With White Powder	Powdery Mildew
Leaves Spotted or Blotched	Fungal Leaf Spot
Crowns and Roots Rot; Odor Present	Crown Rot
Plant Gnawed	Rodent Injury

Plants Rot, Die Over Winter
Balloon flowers don't tolerate cold, soggy soil. It causes the plants to rot at the base or die over the winter. They become more vulnerable to fungal diseases. Add organic matter and sand to lighten soil texture, or remove surviving plants to a better-drained location.

Leaves Mottled, Blotched - Botrytis Gray Mold
This fungus attacks leaves of balloon flowers in cool, damp conditions. Control it by thinning plants to improve air circulation, moving them to a sunnier location, or improving drainage. Pick off all damaged leaves and dust the plants with powdered sulfur. Dig up and discard in the trash individual plants that seem to catch this disease year after year. For more information see the file on Controlling Fungal Disease

Powdery Spots On Leaves; Yellowing - Rust
Rust diseases caused by various fungi produce pale yellow areas on upper leaf surfaces and powdery spots of fruiting bodies on undersides directly beneath. Infected balloon flower stems and flowers may be seriously deformed. Remove any infected leaves as soon as possible. Remove and destroy all garden debris before plants start to grow in the spring. Control weeds in and around the garden. Rust can be prevented by periodic sprays of wettable sulfur on vulnerable plants, starting several weeks before the disease normally appears. Space plants widely apart for good ventilation, and avoid wetting the foliage when watering. For more information see the file on Controlling Fungal Disease

Leaves Covered With White Powder - Powdery Mildew
Powdery mildews are caused by fungi that live on the surface cells of the plant, not inside them. Infected balloon flower leaves are covered with a white or ash-gray powdery mold. Badly infected ones become discolored and distorted, then drop off. Powdery mildews thrive in both very humid or very dry weather. Spray affected plants thoroughly with wettable sulfur once or twice at weekly intervals starting as soon as the whitish coating of the fungus appears. Allow ample spacing between plants and collect and discard all aboveground refuse in the fall. For more information see the file on Controlling Fungal Disease

Leaves Spotted Or Blotched Fungal Leaf Spot
Many kinds of leaf spots are caused by fungi that thrive on moist leaf surfaces and cause transparent to brown or black spots that disfigure the leaves. Some fungal spots are surrounded by flecks or black dots, their spore-bearing fruiting bodies. Often spots come together to form larger patches of dead tissue. Pick off and discard infected balloon flower leaves. Remove dead plant debris promptly from the garden to reduce over-wintering spore populations. Dig up and discard seriously infected plants together with their surrounding soil. Mulching helps prevent splash-borne infection in outdoor plantings. Spray at weekly to 10 day intervals with wettable sulfur, particularly in wet weather. For more information see the file on Controlling Fungal Disease

Crowns and Roots Rot; Odor Present
Crown and root rot, caused by soil-dwelling bacteria and fungi, is the most common balloon flower disease. Suspect it if no shoots appear in the spring (remembering that this plant emerges relatively late normally). A bacteria attacks a few spots on the crown where the roots meet the stems, and then spreads to the entire crown, turning it into a malodorous mush. It may also then be invaded by fungi. If the plant is already in leaf, the lower leaves are discolored and the young shoots begin to wilt. The roots are blackened, rotten and covered with white fungal threads. The whole plant dies in a few days. Remove and discard in the trash all infected plants and their nearby soil. Do not replant balloon flowers in the same place for awhile. Enrich the soil with compost, if it is available, which has fungus fighting qualities. Thoroughly cultivating around plants allows the soil to dry out and hinders the spread of the fungus. This disease is most likely to occur in the late winter thaw when dead leaves decompose on the ground and harbor bacteria and fungi that spread to healthy tissue. Keep winter mulch away from plant crowns to reduce problems.