Iris versicolor

Iris versicolor

Blue Flag, Harlequin Blueflag, Larger Blueflag, Northern Blue Flag

Iris pseudacorus

Iris pseudacorus

Pale Yellow Iris, Yellow Flag

Iris ensata

Iris ensata

Ensata Japanese Iris, Japanese Iris

Iris foetidissima

Iris foetidissima

Gladdon, Gladwin Iris, Roast Beef Plant, Stinking Iris

Iris crocea

Iris crocea

German Iris, Golden Flag

Iris magnifica

Iris magnifica f. caerulea

var. f. caerulea

Blue Juno Iris

Iris bloudowii

Iris bloudowii

Yellow Mongolian Iris

Iris magnifica

Iris magnifica

Juno Iris

Iris sibirica

Iris sibirica

Siberian Iris

Baptisia australis

Baptisia australis

Blue False Indigo, Blue Wild Indigo, Horse Fly Weed, Indigo Weed, Rattlebush, Rattleweed

Ipomoea tricolor

Ipomoea tricolor Heavenly Blue

'Heavenly Blue'

Heavenly Blue Morning Glory

Lobelia siphilitica

Lobelia siphilitica

Blue Cardinal Flower, Great Blue Lobelia

Centaurea montana

Centaurea montana Mountain Blue

'Mountain Blue'

Mountain Bluet, Perennial Cornflower

Hosta ventricosa

Hosta ventricosa

Blue Hosta, Blue Plantain Lily, Hosta

Liriope muscari

Liriope muscari db

Big Blue Lilyturf, Lilyturf

Lupinus polyphyllus

Lupinus polyphyllus

Big-leaved Lupine, Bigleaf Lupine, Blue Bonnet, Blue-pod Lupine, Bog Lupine, Common Lupine , Garden Lupine, Large-leaved Lupine, Lupin, Meadow Lupine

Verbena hastata

Verbena hastata

American Vervain, Blue Vervain, False Vervain, Indian Hyssop, Swamp Verbena, Swamp Vervain, Vervain, Wild Hyssop

Viola sororia

Viola sororia

Butterfly Violet, Common Blue Violet

Aconitum napellus

Aconitum napellus

Monk's Hood, Monk's-hood , Venus' Chariot

Aquilegia caerulea

Aquilegia caerulea

Colorado Blue Columbine, Colorado Columbine, Rocky Mountain Columbine

Cichorium intybus

Cichorium intybus

Chicory

Eryngium planum

Eryngium planum

Blue Eryngo, Flat Sea Holly, Flat-leaved Eryngium

Knautia arvensis

Knautia arvensis

Blue Buttons, Field Scabiosa, Field Scabious

Lobelia siphilitica

Lobelia siphilitica Alba

var. Alba

Great White Blue Lobelia, White Cardinal Flower, White Lobelia