Diagnosing Perennial Sunflower Decline: Aphids, Stalk Rot, or Something Else?

A perennial sunflower north of Toronto (Zone 5) has dry, curled leaves on some branches. Daisies nearby are healthy.

Check for Aphids

• Look under leaves: tiny green/white/yellow flecks.
• If present: spray insecticidal soap or blast with hose. Cut dead tips.
• Watch daisies—aphids may migrate.

If No Aphids

• Could be stalk rot (fungal). Treat with fungicide.

Identify the pest first; treat accordingly.