Aconite (Monkshood, Wolfsbane)
Aconitum spp.

Bachelors Buttons (Bachelor's Buttons, Mountain Cornflower, Perennial Cornflower)
Centaurea spp.; esp. Centaurea cyanus and Centaurea montana

Blue Sowthistle (Blue Sow Thistle, Common Blue Sowthistle, Alpine Blue-sow-thistle)
Cicerbita, esp. C. macrophylla, C. alpina, C. plumieri

Blue Star Creeper (Swamp Isotome, Matted Pratia)
Pratia pedunculata; syn. Isotoma fluviatilis, Lobelia fluviatilis, Laurentia fluviatilis

Blue-eyed Grass (Blue Eye Grass, Blue Eyed Grass, American Blue-eyed Grass)
Sisyrinchium angustifolium, Sisyrinchium montanum

Bluebell (English Bluebell, Spanish Bluebell)
Hyacinthoides non-scripta/Hyacinthoides hispanica

Brunnera (Siberian Bugloss, False Forget-me-not)
Brunnera spp.

Bugle (Ajuga, Bugleweed)
Ajuga reptans; Ajuga Pyramidalis

Caryopteris (Blue Mist, Blue Mist Spirea)
Caryopteris

Ceanothus (Blue Brush)
Ceanothus spp.

Ceratostigma (Chinese Plumbago)
Ceratostigma spp.

Chicory (Wild Chicory, Common Chicory)
Cichorium intybus

Chinese Forget-Me-Not (Chinese Forget Me Not, Chinese Hound's Tongue)
Cynoglossum amabile

Corn Salad (Lamb's Lettuce; Lambs Lettuce)
Valerianella spp., esp. Valerianella locusta

Endive (Belgium Endive, Chicory)
Chicorum endivia

Flax (Linum, Linseed)
Linum spp.

Forget-Me-Not (Forget Me Not, Scorpion Grass)
Myosotis spp.

Gentian (Bitterwort, Bitter Root)
Gentiana spp.

Grape Hyacinth
Muscari spp.

Green Alkanet (Alkanet, Evergreen Bugloss)
Pentaglottis sempervirens

Herb Hyssop (Hyssop)
Hyssopus officinalis

Lamb's Lettuce (Lambs Lettuce)
Valerianella locusta; syn. Valerianella olitoria

Love-In-A-Mist (Love in a Mist)
Nigella damascena

Meconopsis (Himalayan Poppy, Himalayan Blue Poppy)
Meconopsis betonicifolia; M. gakyidiana; M. bailey

Plumbago (Leadwort)
Plumbago spp.

Scilla/Squill
Scilla spp.

Sea Holly
Eryngium spp; esp. Eryngium maritimum and Eryngium bourgatii

Speedwell
Veronica spp., esp. Veronica arvensis

Viper's Bugloss (Vipers Bugloss)
Echium vulgare