Identifying Yellow Cosmos: A Tall, Self-Seeding Annual for Hot Climates

Key Features of Cosmos sulphureus

Tall (4–6 ft), branching stems with terminal yellow/orange flowers. Ferny foliage. Blooms summer to frost.

Self-sows aggressively in warm, moist climates. Listed as invasive in some states.

Deadhead before seed set. Pull volunteers early. In Phoenix, it may be less aggressive due to aridity.

semi closeup blossom and foliage

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