Blue Chiffon® rose of Sharon. Photo by: Proven Winners.

Dutch painter Vincent Van Gogh may not have been a gardener, but he was clearly an admirer of blue flowers, perfectly capturing their beauty in his famous painting Irises (1889). Perhaps as an artist he knew Mother Nature’s secret to producing “true" blue flowers, which is actually a blend of plant pigments that reflect light in such a way to create the illusion of natural blue. (Even flowers can benefit from the right lighting!)

Making up less than 10% of the flowering plant kingdom, plants with blue blooms are a rarity, but you still have many options. This elite color group includes a wide range in shades ranging from sky blue to deep indigo and growth habits from groundcovers to large shrubs. And if you plan carefully, your garden will be singing the blues from early spring through late fall.

Photo by: Proven Winners.

HYDRANGEA

Let's Dance® Rhythmic Blue® HydrangeaBuy now from Proven Winners
Hydrangea macrophylla

This reblooming hydrangea produces huge mophead flowers all summer, without pruning. It also performs well in colder climates. For the best blue, keep your soil acidic and treat with aluminum sulfate.

Plant Type / Zones: Shrub, Zones 5-9
Size: 3 to 4 feet tall and wide
Bloom time: Midsummer to early fall
Exposure: Full sun to partial shade

Learn more about growing hydrangeas.

Photo by: Proven Winners.

SALVIA

Rockin'® Playin' the Blues® SalviaBuy now from Proven Winners
Salvia hybrid

When the flowers finish blooming, the color continues because the calyxes retain their deep-blue hue long after the flowers fade. Even better, new flower spikes continue to emerge all summer long.

Plant Type / Zones: Perennial in Zones 7-10; usually grown as an annual
Size: 2 to 4 feet tall, 2 to 3 feet wide
Bloom time: Planting until frost
Exposure: Full sun to partial shade

Learn more about growing salvia.

Photo by: Proven Winners.

LILY OF THE NILE

Little Galaxy Lily of the NileBuy now from Proven Winners
Agapanthus hybrid

This more compact, blue-flowered wonder produces huge, globe-like flower clusters held high above clumps of narrow leaves. The seedpods that follow are almost as attractive as the flowers.

Plant Type / Zone: Perennial, Zones 6-11
Size: 22 to 26 inches tall and wide
Bloom time: July to September
Exposure: Full sun

Learn more about growing lily of the Nile.

Photo by: Proven Winners.

ROSE OF SHARON

Blue Chiffon® Rose of SharonBuy now from Proven Winners
Hibiscus syriacus

Blue Chiffon gives you lacy blooms from summer to fall on soft, elegant stems. Its flowers attract birds and butterflies and have a delicate, lacy center. Heat and drought tolerant.

Plant Type / Zones: Shrub, Zones 5-9
Size: 8 to 12 feet tall, 4 to 6 feet wide
Bloom time: Early to late summer
Exposure: Full sun

Learn more about growing rose of Sharon and hardy hibiscus.

Photo courtesy American Meadows.

CORNFLOWER

Blue Cornflower
Centaurea cyanus

Also called “bachelor’s buttons," this old-fashioned favorite is popular in cutting gardens. The blue color is so distinctive, it has been replicated in a Crayola crayon.

Plant Type: Annual
Size: 1 to 3 feet tall, 10 inches wide
Bloom time: Peak bloom is early to midsummer, may be prolonged with frequent deadheading.
Exposure: Full to partial sun

Photo by: Proven Winners.

DWARF MORNING GLORY

Blue My Mind® Dwarf Morning GloryBuy now from Proven Winners
Evolvulus hybrid

This non-vining cousin of morning glory produces dainty true-blue blooms from early summer until the first frost, but only spreads no more than 2 feet.

Plant Type / Zones: Perennial in Zones 10-11; usually grown as an annual
Size: 6 to 12 inches tall, trails up to 2 feet
Bloom time: Planting until frost
Exposure: Full sun

Photo by: Millette Rejean D / Millette Photomedia.

IRIS

’Blue Suede Shoes’ Bearded Iris
Iris germanica 'Blue Suede Shoes'

This spectacular sapphire-blue iris has large ruffled blooms, accented by bright yellow beards. They make their debut in the spring only to come back again later in the summer.

Plant Type / Zone: Perennial, Zones 5-9
Size: 36 to 39 inches tall, up to 2 feet wide
Bloom time: Mid to late spring and again in late summer
Exposure: Full sun

Learn more about growing irises.

Photo by: Proven Winners.

LOBELIA

Laguna® Sky Blue LobeliaBuy now from Proven Winners
Lobelia erinus

One of the best blue-flowered container plants, producing cascades of tiny soft-blue flowers from spring until the first frost. This heat-tolerant variety is also bred to withstand sultry summer temperatures.

Plant Type / Zones: Perennial in Zones 9-11; usually grown as an annual
Size: 6 to 12 inches tall, spreading up to 2 feet
Bloom time: Spring until frost
Exposure: Full sun to partial shade

Learn more about growing lobelia.

Photo by: Proven Winners.

GENTIAN

Gentiana ‘True Blue’Buy now from Proven Winners
Gentian hybrid

This gentian’s blooms are a brilliant royal blue, set off by attractive emerald-green lance-shaped leaves. The tubular, upward-facing flowers bloom in profusion all along the stems.

Plant Type / Zones: Perennial, Zones 4-7
Size: 24 to 30 inches tall, 12 to 18 inches wide
Bloom time: Midsummer to early fall
Exposure: Full sun to part shade; protect from afternoon sun in climates with hot, humid summers.

Photo by: Millette Rejean D / Millette Photomedia.

LOVE-IN-A-MIST

Love-in-a-Mist
Nigella damascena

With its delicate flowers, ferny foliage, and ornamental seedpods, this classic cottage garden flower is a favorite for fresh and dried cut-flower arrangements.

Plant Type: Annual
Size: 1 to 2 feet tall, up to a foot wide
Bloom time: Spring through early summer
Exposure: Full sun

Photo by: mizy / Shutterstock.

BRUNNERA

‘Jack Frost’ Siberian BuglossBuy now from Proven Winners
Brunnera macrophylla

Also called heartleaf brunnera and false forget-me-not, this shade-loving beauty is grown as much for its foliage as it is for its lovely sprays of tiny baby-blue flowers.

Plant Type / Zone: Perennial, Zones 3-8
Size: 12 to 15 inches tall and wide
Bloom time: Late April to June
Exposure: Shade to partial sun.

Photo by: Proven Winners.

GLOBE THISTLE

Blue Glow Globe ThistleBuy now from Proven Winners
Echinops spp.

The spiky, golfball-sized flower heads make a bold statement, both in the garden and in floral arrangements. The blooms look similar to ornamental onions, they emerge later in the summer.

Plant Type / Zones: Perennial, Zones 4-9
Size: 4 feet tall, up to 2 feet wide
Bloom time: Late June to September
Exposure: Full sun

Photo by: Proven Winners.

DELPHINIUM

Summer Cloud DelphiniumBuy now from Proven Winners
Delphinium grandiflorum

Breathtaking blue flowers all summer long. Selections in the grandiflorum group have a more compact growth habit, so they never need staking, as well as better heat tolerance during the dog days of summer.

Plant Type / Zone: Perennial, Zones 3-7
Size: 12 to 18 inches tall and wide
Bloom time: Late spring through summer
Exposure: Full sun

Learn more about growing delphiniums.

Photo by: Proven Winners.

FALSE INDIGO

Decadence® 'Blueberry Sundae' False IndigoBuy now from Proven Winners
Baptisia australis

Tough, drought tolerant, and produces spires of flowers in late spring that last well into summer. The indigo-blue flowers are set off by vase-shaped mounds of blue-green foliage.

Plant Type / Zone: Perennial, Zones 3-9
Size: 2-1/2 to 3 feet tall and wide
Bloom time: Late May to July
Exposure: Best flowering occurs in full sun, but can tolerate some shade.

Learn more about growing baptisia.

Photo by: Proven Winners.

BLUEBEARD

Beyond Midnight® BluebeardBuy now from Proven Winners
Caryopteris x clandonensis

This compact shrub produces an abundance of blue flowers late into the season. Clusters of fragrant, deep-blue flowers last well into autumn. A favorite of butterflies and other pollinators.

Plant Type / Zones: Shrub, Zones 5-9
Size: 2 to 3 feet tall and wide
Bloom time: Midsummer through fall
Exposure: Full sun

Photo by: SKPG_Arts / Shutterstock.

VIRGINIA BLUEBELLS

Virginia Bluebells
Mertensia virginica

Bright pink buds open into delicate sky-blue bells on this spring-blooming native wildflower. Naturalizes easily, goes dormant in summer, but will return with vigor in spring.

Plant Type / Zone: Perennial, Zones 3-8
Size: 12 to 18 inches tall and wide
Bloom time: April to May
Exposure: Filtered shade

Photo by: Proven Winners.

BELLFLOWER

‘Rapido Blue’ Carpathian BellflowerBuy now from Proven Winners
Campanula carpatica

This blue-flowered, ground-covering perennial becomes smothered with upturned, bell-shaped flowers in spring, creating a colorful carpet that lasts through most of the summer.

Plant Type / Zone: Perennial, Zones 3-8
Size: 5 to 7 inches tall, 5 to 8 inches wide
Bloom time: Early spring to summer
Exposure: Full sun; prefers afternoon shade in warmer climates

Photo by: Proven Winners.

ASTER

Peachie's Pick Stokes’ Aster Buy now from Proven Winners
Stokesia hybrid

This prolific native wildflower sports lavender-blue flowers that continue nonstop until the first frost, especially if deadheaded regularly.

Plant Type / Zones: Perennial, Zones 5-9
Size: 18 inches tall, 18 to 24 inches wide
Bloom time: July through September
Exposure: Full sun

Learn more about growing asters.

Photo by: Proven Winners.

SPIKE SPEEDWELL

Magic Show® ‘Wizard of Ahhs’ spike speedwellBuy now from Proven Winners
Veronica hybrid

Although speedwell flowers come in a variety of colors, those with dark blue flowers are often the most arresting. ‘Wizard of Ahhs’ is prized for its exceptionally long bloom time.

Plant Type / Zones: Perennial, Zones 3-9
Size: 18 to 24 inches tall and wide
Bloom time: June to September
Exposure: Full sun

Learn more about growing speedwell.

Photo by: Proven Winners.

FELICIA DAISY

‘Cape Town Blue’ Blue Felicia DaisyBuy now from Proven Winners
Felicia hybrid

Heavenly sky-blue petals surround yellow centers on this compact-growing daisy. The bloom season lasts all summer into fall, even without deadheading.

Plant Type / Zones: Perennial in Zones 10-11; usually grown as an annual
Size: 8 to 12 inches tall, 10 to 12 inches wide
Bloom time: Planting until frost
Exposure: Full sun to part shade

RELATED:
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20 Purple Flowers to Brighten Your Garden
How to Start a Flower Garden

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