Late Summer

Plants that bloom in August in Zone 3 with blue flowers

15 plants match

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All Zone 3 plantsAll blue flowersAll August blooms
AsterPerennialAug-Nov
Aster
The grand finale of the garden season. Essential for fall pollinators.
Z3-8
Big BluestemGrassAug-Oct
Big Bluestem
The signature grass of the tallgrass prairie, turning copper-bronze in fall with distinctive turkey-foot seed heads.
Z3-9
BorageAnnualJun-Sep
Borage
Star-shaped electric blue flowers that bees go absolutely wild for. Self-sows freely.
Z2-11
CampanulaPerennialJun-Aug
Campanula
Open, nodding bells in clear blue on tall graceful stems. Self-sows into refined cottage garden drifts.
Z3-8
Cat's Meow CatmintPerennialMay-Sep
Cat's Meow Catmint
Tidy, dome-shaped habit that never flops open. Stays compact without shearing.
Z3-9
CatmintPerennialMay-Sep
Catmint
Billowy lavender-blue haze that blooms all season if you shear it back.
Z3-10
ClematisVineMay-Sep
Clematis
The queen of flowering vines. Over 300 species, something for every spot.
Z3-10
Globe ThistlePerennialJul-Aug
Globe Thistle
Perfectly spherical steel-blue globes on white stems that dry to perfection. Bees are absolutely obsessed.
Z3-9
MonkshoodPerennialAug-Sep
Monkshood
Deep indigo-blue hooded flowers on tall spikes in late summer. One of the few genuinely blue flowers that grows in shade.
Z3-7
Morning GloryAnnualJun-Oct
Morning Glory
Fast-climbing vine with trumpets that open fresh every morning.
Z3-10
Mountain BluebellPerennialJun-Aug
Mountain Bluebell
Sky-blue bell flowers on tall arching stems along mountain streams. The showy western cousin of Virginia Bluebell.
Z3-7
PickerelweedPerennialJun-Sep
Pickerelweed
Spikes of violet-blue flowers above glossy arrow-shaped leaves. Native pond and stream bank staple.
Z3-10
SalviaPerennialMay-Sep
Salvia
Vertical flower spikes that hummingbirds and bees cannot resist.
Z3-10
SpeedwellPerennialMay-Aug
Speedwell
Tidy spikes of blue that add vertical punch to the front of the border.
Z3-8
Walker's Low CatmintPerennialMay-Sep
Walker's Low Catmint
Perennial Plant of the Year. Billowy lavender-blue spikes that rebloom hard after a shear.
Z3-9
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