Plants that bloom in September in Zone 11 with purple flowers

Bougainvillea

Explosive cascades of papery magenta, hot pink, or coral bracts that smother walls, fences, and pergolas with nonstop color from spring through fall in zones 9 to 11.

Calibrachoa

Mini petunias that bloom nonstop in hanging baskets. Dozens of color options and no deadheading needed.

Cleome

Spider-flower with whisker-like stamens and airy blooms. Tall, dramatic annual that self-sows freely.

Tall Verbena

Wiry stems topped with purple clusters that butterflies can't resist. See-through plant for layering.