Flowers come in a huge range of colours, but blue blooms are relatively rare. Let them add some mystery and interest to your border where you can admire the calming blue tones.
Whether you want sky blue, royal blue or purple-blue, there’s a cool colour to boost your beds, borders and containers.
1. Gentiana ‘Blue Silk’ (gentian)
This gorgeous semi-evergreen with narrow leaves and blue upward-facing funnel-shaped flowers have stripes of purple to add even more interest. Fitting in a cottage and courtyard gardens, they’ll add some pretty purple-blue colour.
• Sun – Full sun or partial shade
• Position – South, North, East or West facing
• Exposure – Exposed or sheltered
• Moisture – Moist but well-drained
• Soil – Loam or sand
2. Delphinium ‘Blue Lace’
The iconic blue plant, its columnar, upright habit makes this tall perennial perfect for the back of the border, where it can grow up to 2.5m tall.
• Sun – Full sun
• Position – South, West or East facing
• Exposure – Sheltered
• Moisture – Moist but well-drained
• Soil – Sand, chalk, loam or clay
3. Campanula cochlearifolia (fairy thimbles)
Low maintenance and low growing, the clump-forming perennial has bright green leaves that are joined by light blue flowers on top of thin stems, growing up 10cm tall. They will feel right at home in a rock garden or at the front of a sunny border.
• Sun – Full sun or partial shade
• Position – South, North, West or East facing
• Exposure – Exposed or sheltered
• Moisture – Well-drained or moist but well-drained
• Soil – Loam, chalk or sand
4. Salvia patens (gentian sage)
These rich, blue flowers have two lips, and bloom on an up right stem, growing up to 1m tall. Flowering through summer and autumn, it packs a real punch in a wall-side border or added to a Mediterranean style garden.
• Sun – Full sun
• Position – South or East facing
• Exposure – Sheltered
• Moisture – Moist but well-drained
• Soil – Chalk, loam or sand
5. Agapanthus ‘Royal Blue’ (African lily)
The violet-blue tones of the bell-shaped flowers bloom in late summer and add some charm to containers where they can grow to 1m. They are a low maintenance plant, needing no pruning apart from deadheading flower stems.
• Sun – Full sun
• Position – South, West or East facing
• Exposure – Sheltered
• Moisture – Moist but well-drained
• Soil – Loam, chalk or sand
6. Iris ‘Harmony’ (iris)
The royal blue flowers with yellow markings bloom in early spring. Growing to 12cm tall, situating them at the front of a border in a cottage garden will be suitable for these hardy plants.
• Sun – Full sun
• Position – South, North, West or East facing
• Exposure – Sheltered
• Moisture – Well-drained or moist but well-drained
• Soil – Chalk, clay, sand or loam
7. Triteleia laxa (triplet lily)
Blooming star-shaped purple-blue flowers in early summer, these are a great addition to a cottage garden or informal garden. Plant them in autumn 8cm deep and protect from frosts and winter chills to ensure they are ready and raring to go in summer.
• Sun – Full sun
• Position – South, West or East facing
• Exposure – Sheltered
• Moisture – Well-drained
• Soil – Loam or sand
8. Felicia amelloides (Kingfisher daisy)
With striking blue daisy flowers with vibrant yellow centres, this low-growing variety is a great option for ground cover or garden edging where they can grow up to 1m tall with thin leafless stems.
• Sun – Full sun
• Position – South or West facing
• Exposure – Exposed
• Moisture – Well-drained
• Soil – Loam, chalk or sand
9. Sollya heterophylla (bluebell creeper)
This is an evergreen climber with dainty bell-shaped flowers that hang gently down, and it also produces purple berries in autumn. The plant will need support as it climbs to add some charm and character to your wall-side border.
• Sun – Full sun or partial shade
• Position – South, West or East facing
• Exposure – Sheltered
• Moisture – Well-drained, moist but well-drained
• Soil – Loam, chalk or sand
10. Tweedie coerulea (blue tweedia)
An unusual scrambling, twining plant with evergreen foliage, it produces sky-blue star-shaped flowers in small clusters. It’s not hardy but can be grown in frost-free areas or treated as an annual.
• Sun – Full sun
• Position – South, West or East facing
• Exposure – Sheltered
• Moisture – Well-drained or moist but well-drained
• Soil – Loam, chalk or sand
With these brilliant blue blooms, you will be sure to add some rarity and magic to your beds and borders, whether you have a classic cottage garden or are opting for a Mediterranean haven.
David Domoney is a Chartered Horticulturalist, Broadcaster, and Author. David has worked with a number of the UK’s leading garden retailers as a plant buyer and strategic consultant. With more than 30 years experience, in horticulture, David is as passionate about plants now as he was when he bought his first plant at a village fete.
My favourite blue ‘flower’ is my Eryngium, the stem also turns the same vibrant shade of blue as the flower matures. Stunning. Thereafter it has to be Agapanthus Bressingham Blue.