 | Eryngium tricuspidatum
Sea Holly | Herbaceous Flowers, Container-friendly, Upright - Clump | Dark blue flowers (Summer), Silver foliage |
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 | Echinops setifer
Echinops | Herbaceous Flowers, Upright - Clump | Dark blue flowers (Summer late), Dark Green foliage |
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 | Ajuga reptans
Bugle, Ajuga | Herbaceous Flowers, Ground cover, Container-friendly, Spreading ground hugging | Dark blue flowers (Spring), Purple foliage |
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 | Ceratostigma plumnaginoides
Hardy Plumbago, Ceratostigma | Herbaceous Flowers, Ground cover, Container-friendly, Spreading clump | Dark blue flowers (Summer late), Dark Green foliage |
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 | Onopordon acanthium
Scotch Thistle, Onopordon | Herbaceous Flowers, Spikey | Dark blue flowers (Summer), Silver foliage |
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 | Salvia x sylvestris
'Mainacht'
Sage | Herbaceous Flowers, Ground cover, Container-friendly, Rounded - Clump | Dark blue flowers (Summer late), Medium Green foliage |
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 | Lupinus
'Gallery Blue'
Lupin | Herbaceous Flowers, Rounded - Clump | Dark blue flowers (Summer), Medium Green foliage |
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 | Nepeta racemosa
'Walkers Low'
Catnip, Nepeta | Herbaceous Flowers, Herbs, Ground cover, Culinary, Container-friendly, Spreading arching | Dark blue flowers (Summer early, scented), Grey foliage |
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 | Geranium clarkei
'Kashmir Blue'
Cranesbill | Herbaceous Flowers, Ground cover, Container-friendly, Rounded - Clump | Dark blue flowers (Summer), Medium Green foliage |
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 | Geranium renardii | Herbaceous Flowers, Ground cover, Container-friendly, Rounded - Clump | Dark blue flowers (Summer), Medium Green foliage |
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