Azure Monkshood	Aconitum carmichaelii
Azure Monkshood	Aconitum carmichaelii 'Arendsii'
Common Monkshood	Aconitum napellus
Lilyleaf Ladybells	Adenophora lilifolia
Blue Fortune Agastache	Agastache 'Blue Fortune'
Anise Hyssop	Agastache foeniculum
Fragrant Delight Hyssop	Agastache foeniculum 'Fragrant Delight'
Black Hollyhock	Alcea rosea 'Nigra'
Allium Globemaster	Allium 'Globemaster'
Allium Purple Sensation	Allium 'Purple sensation'
Arkansas Amsonia (Bluestar)	Amsonia hubrectii
Willow Amsonia	Amsonia tabernaemontana
Willowleaf Amsonia	Amsonia tabernaemontana var. salicfolia
Sky Blue Aster	Aster azureus
Blue Lagoon Aster	Aster 'Blue Lagoon'
Ideal Wood Blue Aster	Aster cordifolius 'Ideal'
Erlkonig Aster	Aster ericoides 'Erlkonig'
Frikart's Aster	Aster x frikartii 'Monch'
Smooth Blue Aster	Aster laevis
Little Carlow Aster	Aster 'Little Carlow'
Big-Leaved Aster	Aster macrophyllus
Purple Dome New England Aster	Aster novae-angliae 'Purple Dome'
New York Aster	Aster novi-belgii
Celeste New York Aster	Aster novi-belgii 'Celeste'
Eventide New York Aster	Aster novi-belgii 'Eventide'
Lady in Blue New York Aster	Aster novi-belgii 'Lady in Blue'
Marie Ballard New York Aster	Aster novi-belgii 'Marie Ballard'
Sailor Boy New York Aster	Aster novi-belgii 'Sailor Boy'
Aromatic Aster	Aster oblongifolius
October Skies Aster	Aster oblongifolius 'October Skies'
Raydon's Favorite Aster	Aster oblongifolius 'Raydon's Favorite'
Tatarian Aster	Aster tataricus 'Jindai'
Prarie Aster	Aster turbinellus
Wood's Blue Aster	Aster 'Wood's Blue'
Wood's Light Blue Aster	Aster 'Wood's Light Blue'
Wood's Purple Aster	Aster 'Woods Purple'
Dwarf Chinese Astilbe	Astilbe chinensis 'Pumila'
Wild Blue Indigo	Baptisia australis
Purple Smoke Indigo	Baptisia 'Purple Smoke'
Heartleaf Brunnera (Siberian Bugloss)	Brunnera macrophylla
Jack Frost Siberian Bugloss	Brunnera macrophylla 'Jack Frost'
Langtress Siberian Bugloss	Brunnera macrophylla 'Langtrees'
Butterfly Bush	Buddleia alternifolia
Black Knight Butterfly Bush	Buddleia davidii 'Black Knight'
Dartmore Butterfly Bush	Buddleia davidii 'Dartmore'
Nanho Blue Butterfly Bush	Buddleia davidii 'Nanho Blue'
Nanho Purple Butterfly Bush	Buddleia davidii 'Nanho Purple'
Thread-leaved Purple Poppy Mallow	Callirhoe involucrata var. tenuissima
Birch's Bellflower	Campanula 'Birch's Hybrid'
Blue Clips Bellflower	Campanula carpatica 'Blue Clips'
Telham Beauty Peachleaf Bellflower	Campanula persicifolia 'Telham Beauty'
Serbian Bellflower	Campanula poscharskyana
Chimney Bellflower	Campanula pyramidalis
Blue Mist Shrub	Caryopteris clandonensis
Arthur Simmonds Blue Mist Shrub	Caryopteris clandonensis 'Arthur Simmonds'
Dark Knight Blue Mist Shrub	Caryopteris clandonensis 'Dark Knight'
First Choice Blue Mist Shrub	Caryopteris clandonensis 'First Choice'
Variegated Blue Mist Shrub	Caryopteris divaricata 'Snow Fairy'
Mountain Bluet	Centaurea montana
Globe Artichoke	Cynara cardunculus
Magic Heavenly Blue Delphinium	Delphinium 'Magic Heavenly Blue'
Peace Delphinium	Delphinium 'Peace'
Purple Coneflower	Echinacea purpurea
Kim's Knee High Purple Coneflower	Echinacea purpurea 'Kim's Knee High'
Magnus Purple Coneflower	Echinacea purpurea 'Magnus'
Ruby Star Purple Coneflower	Echinacea purpurea 'Rubinstern'
Small Globethistle	Echinops ritro
Hardy Ageratum	Eupatorium coelestinum
Cori Hardy Ageratum	Eupatorium coelestinum 'Cori'
Johnson's Blue Geranium	Geranium x 'Johnson's Blue'
Bevan's Bigroot Geranium	Geranium macrorrhizum 'Bevan's Variety'
Czakor Bigroot Geranium	Geranium macrorrhizum 'Czakor'
Blood Red Geranium	Geranium sanguineum
New Hampshire Blood Red Geranium	Geranium sanguineum 'New Hampshire'
Always Afternoon Daylily	Hemerocallis 'Always Afternoon'
Blue Sheen Daylily	Hemerocallis 'Blue Sheen'
Catherine Woodbury Daylily	Hemerocallis 'Catherine Woodbury'
Lady Eva Daylily	Hemerocallis 'Lady Eva'
Purple de Oro Daylily	Hemerocallis 'Purple de Oro'
Summer Wine Daylily	Hemerocallis 'Summer Wine'
Can Can Coral Bells	Heuchera 'Can Can'
Sweet Iris (Variegated Iris)	Iris pallida 'Variegata'
Dreaming Spires Iris	Iris sibirica 'Dreaming Spires'
Lavender	Lavandula angustifolia
Lady Lavender	Lavandula angustifolia 'Lady'
Lavender Lady Lavender	Lavandula angustifolia 'Lavender Lady'
Munstead Lavender	Lavandula angustifolia 'Munstead'
Rocky Mountain Gayfeather	Liatris ligulistylis
Prarie Blazingstar	Liatris pycnostachya
Spike Gayfeather	Liatris spicata 'Kobald'
Sea Lavender	Limonium latifolium
Purple Lobelia	Lobelia x gerardii 'Vedariensis'
Grape Knee-High Lobelia	Lobelia 'Grape Knee-High'
Great Blue Lobelia	Lobelia siphilitica
Rose Campion	Lychnis coronaria
Virginia Bluebells	Mertensia virginica
Aquarius Bee Balm	Monarda didyma 'Aquarius'
Blue Stocking Bee Balm	Monarda didyma 'Blue Stocking'
Claire Grace Bee Balm	Monarda didyma 'Claire Grace'
Violet Queen Bee Balm	Monarda didyma 'Violet Queen'
Catmint	Nepeta
Blue Wonder Cat Mint	Nepeta x faassenii 'Blue Wonder'
Dawn to Dusk Catmint	Nepeta x faassenii 'Dawn to Dusk'
Six Hills Giant Cat Mint	Nepeta x faassenii 'Six Hills Giant'
Walker's Low Cat Mint	Nepeta x faassenii 'Walker's Low'
Mauve Catmint	Nepeta mussinii
Russian Sage	Perovskia atriplicifolia
Little Spire Russian Sage	Perovskia atriplicifolia 'Little Spire'
Amethyst Garden Phlox	Phlox paniculata 'Amethyst'
Blue Boy Garden Phlox	Phlox paniculata 'Blue Boy'
Blue Paradise Garden Phlox	Phlox paniculata 'Blue Paradise'
Katherine Garden Phlox	Phlox paniculata 'Katherine'
Laura Garden Phlox	Phlox paniculata 'Laura'
Miss Margie Garden Phlox	Phlox paniculata 'Miss Margie'
Nicky Garden Phlox	Phlox paniculata 'Nicky'
Sternhimmel Garden Phlox	Phlox paniculata 'Sternhimmel'
Baby Blue Balloon Flower	Platycodon grandiflorus 'Baby Blue'
Double Blue Balloon Flower	Platycodon grandiflorus 'Double Blue'
Fuji Blue Balloon Flower	Platycodon grandiflorus 'Fuji Blue'
Komachi Balloon Flower	Platycodon grandiflorus 'Komachi'
Mariesii Balloon Flower	Platycodon grandiflorus 'Mariesii'
Sentimental Blue Balloon Flower	Platycodon grandiflorus 'Sentimental Blue'
Creeping Jacob's Ladder	Polemonium reptans
Blue Lungwort	Pulmonaria angustifolia
British Sterling Lungwort	Pulmonaria 'British Sterling'
Long-leaved Lungwort	Pulmonaria longifolia cevennensis
Dordogne Lungwort	Pulmonaria longifolia 'Dordogne'
Roy Davidson Lungwort	Pulmonaria 'Roy Davidson'
Azure Sage	Salvia azurea var. grandifolia
Lyre-leaved Sage	Salvia lyrata 'Purple Knockout'
Caradonna Sage	Salvia nemorosa 'Caradonna'
Lubeca Sage	Salvia nemorosa 'Lubeca'
Blue Hill Sage	Salvia x superba 'Blauhugel'
May Night Sage	Salvia x superba 'May Night'
Purple Rain Sage	Salvia verticillata 'Purple Rain'
Butterfly Blue Pincushion Flower	Scabiosa columbaria 'Butterfly Blue'
Ultra Violet Pincushion Flower	Scabiosa columbaria 'Ultra Violet'
Big Betony	Stachys macrantha 'Robusta'
Hummelo Betony	Stachys monnieri 'Hummelo'
Klaus Jelitto Stoke's Aster	Stokesia laevis 'Klaus Jelitto'
Lavender Mist Meadowrue	Thalictrum rochebrunianum
Concord Grape Spiderwort	Tradescantia 'Concord Grape'
Sweet Kate Spiderwort	Tradescantia 'Sweet Kate'
Blue Spiderwort	Tradescantia 'Zwanenburg Blue'
Togen Toad Lily	Tricyrtis togen
Western Ironweed	Vernonia fasiculata
Blue John Veronica	Veronica longifolia 'Blue John'
Fuchsia Rose Veronica	Veronica longifolia 'Fuchsia Rose'
Goodness Grows Veronica	Veronica 'Goodness Grows'
Blue Peter Spiked Veronica	Veronica spicata 'Blue Peter'
Wooly Speedwell	Veronica spicata subsp. incana
Royal Candles Spiked Veronica	Veronica spicata 'Royal Candles'
Sunny Border Blue Spiked Veronica	Veronica spicata 'Sunny Border Blue'
Lavendelturm Culver's Root	Veronicastrum virginicum 'Lavendelturm'