Plants that bloom in May in Zone 9 with purple flowers

Ajuga

Bronze-purple foliage with blue spikes. Fills bare shade in one season.

Allium

Dramatic globe-shaped heads on tall stems. Architectural and deer-proof.

Annual Vinca

Glossy-leaved heat champion (botanically unrelated to true Vinca minor) that blooms through humidity that wilts everything else.

Azalea

Explosive spring color in every warm hue. Acid-loving woodland classic.

Bachelor's Button

True cornflower blue that almost no other flower can match. Cottage garden classic that self-sows reliably.

Batik Iris

Streaked and splashed purple-and-white pattern unlike any other iris. Each bloom is unique, like brushwork on silk.

Bloom-a-Thon Azalea

Repeat-blooming azalea with waves of color spring through fall. Evergreen in mild climates.

Blue False Indigo

Lupine-like spikes on a native that lives forever. Gets better with age.

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.

Caesar's Brother Siberian Iris

Tall stems hold rich violet-blue flowers above grassy foliage. The Siberian iris benchmark, blooming earlier and longer than bearded types.

Calibrachoa

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

Caradonna Salvia

Dark purple stems set this apart from every other salvia. Vertical, architectural, electric.

Cat's Meow Catmint

Tidy, dome-shaped habit that never flops open. Stays compact without shearing.

Catmint

Billowy lavender-blue haze that blooms all season if you shear it back.

Chives

Cheerful purple pom-pom flowers on a kitchen staple. Edible blooms make any salad Instagram-worthy.

Clematis

The queen of flowering vines. Over 300 species, something for every spot.

Creeping Phlox

An evergreen sun-loving groundcover that smothers walls, slopes, and rock gardens in dense pink, purple, blue, lavender, or white sheets every April and May.

Dutch Iris

Slender stems bear elegant iris blooms in late spring to early summer.

Encore Autumn Azalea

Spring blooms plus a full fall encore. Multiple color options in the Encore series.

Honesty

Purple spring flowers turn into translucent silvery seed pods like full moons. Biennial cottage classic that self-sows everywhere.

Impatiens

The shade annual champion. Flowers prolifically where nothing else will.

Iris

Elegant sword-leaved perennials with intricate, ruffled blooms.

Lantana

Multi-colored flower clusters that bloom relentlessly in brutal heat.

Larkspur

Tall spires of spurred flowers in deep blue and purple. The annual cousin of delphinium, easier to grow from seed and just as dramatic.

Magnolia

Goblet-shaped blooms on bare branches. One of spring's most dramatic moments.

May Night Salvia

Perennial Plant of the Year. Dense indigo-violet spikes that rebloom if deadheaded.

Native Spiderwort

Three-petaled flowers in blue-purple open fresh each morning on a tough native that blooms for weeks and seeds freely.

Pentas

Star-shaped flower clusters that hummingbirds and butterflies hit on every pass. Blooms nonstop in heat that stops impatiens cold.

Petunia

Cascading color for containers and beds. Blooms nonstop until frost.

Portulaca

Succulent-leaved sun lover with silky rose-like blooms that thrives where pavement, rock, or sand defeats everything else.

Salvia

Vertical flower spikes that hummingbirds and bees cannot resist.

Snapdragon

Vertical flower spikes with squeeze-open blooms. Kids love them.

Stock

Dense spikes of clove-scented blooms in soft pastels. Cool-season cut flower that fills a room with spicy perfume.

Sweet Alyssum

Honey-scented carpet of tiny flowers. The best living edging plant.

Sweet Pea

Ruffled, intensely fragrant climbing flowers in every pastel shade. Cool-season annual that hates heat.

Sweet William

Dense flat clusters in zoned bicolors with a sweet clove fragrance. Old-fashioned cottage charm that returns reliably.

The President Clematis

Big, rich violet-blue flowers with silvery reverse petals rebloom through the season on a vigorous, reliable plant.

Triteleia

Loose umbels of starry blue trumpets on tall wiry stems. Western native bulb that thrives on summer drought.

Vinca

Evergreen mat with periwinkle-blue flowers. Tough shade ground cover.

Wallflower

Velvety blooms in burnished sunset tones with a sweet violet fragrance. The forgotten cottage staple worth bringing back.

Wisteria

Cascading, fragrant racemes that create a dreamy canopy. Needs structure.