From bluebells to forget-me-nots, blue flowers can bring lots of joy to your garden border.
Blue works well with lots of greens and foliage, and combining it with more vibrant colours such as orange or lemon yellow (a classic combination) will look great. If you're looking for more advice on using colour in the garden, why not be inspired by the designs from this small space, where the palette is predominantly green and soft grey?
You may also like
- Pink flowers for the garden you'll love
- 17 of the best orange flowers for a pop of colour
- White flowers to grow
- How to create a dog-friendly garden
18 blue flowers to plant in your garden
Spring season
Lathyrus vernus
The spring vetch is a native to the forests of Siberia, showing that it can always be counted on for hardiness. It is a woodland plant and so prefers a shady position with a humus-rich soil and is easy to propagate from seed. It makes neat clumps, about 40cm high, of elegantly pointed leaves, and
flowers in late February with beautiful purple vetch flowers, tinted with shades of pink and blue.
Season of interest February – May.
Scilla
These work beautifully in combination with lemon-yellow daffodils, and are a delight among shrubs and borders. This blue carpet is a perfect prelude to the bluebells, which flower shortly after, continuing this display. Bulbs can be planted in autumn, but can also be spread around the garden by dividing clumps after flowering. AGM.
Season of interest: March – April.
Cerinthe
Honeywort produces a sweet, honey-flavoured nectar irresistible to bees. It has very unusual bell-shaped, purple flowers, hooded by deep blue-green glaucous leaves. Blooming from spring to autumn, they produce large black seeds that are explosively released, don’t cut back too early and allow it to go to seed if you want it to persist in your garden. It makes an excellent cut flower.
Season of interest: Spring to summer.
Forget-me-not flowers
Forget-me-nots are an easy flower to care for, as they are robust and like to self seed. While not all forget-me-not flowers are blue, the most recognisable of them are. They make good ground cover a spring border and pollinators love them.
Season of interest: Spring to summer
Bluebells
A spring highlight, these native perennial wildflowers have arching stems, lined with nodding bell-shaped blooms. They like moist soil and, because they are woodland plants, will thrive under deciduous trees and shrubs. Be sure to buy bluebells from a reputable supplier. Some bluebells sold as English bluebells are actually Spanish ones. Here's everything you need to know about growing bluebells.
Season of interest: Spring
Camassia
A meadow filled with emerging camassia is a wonderful thing and these lovely blue flowers are hardy, versatile perennials that can be planted in mixed and herbaceous borders, as well as in containers. There are white and purple varieties too, but we love the traditional blue camassia. Most flower from April through to June. Discover how to grow camassia.
Season of interest: Spring to summer
Hepaticum
Dainty, charming and ever so slightly recalcitrant, hepaticas are among the loveliest flowers of spring. The plants are compact and perennial with diverse flowers and intriguingly patterned leaves. It can be a challenge to find the right growing conditions for hepaticas. They grow best in open, fertile, moist soil under trees and shrubs. In the wild, they are often found growing near rivers and streams.
Season of interest: from March to May, earlier if grown in a cold greenhouse.
Corydalis
Many people associate corydalis with yellow, but there are lovely blue options, alongside white and pink cultivars too. It is a delicate, elegant plant that flowers from spring through to summer. Most corydalis you buy in garden centres are the herbaceous perennial woodland plants, so they will like shade over summer. Here's our grow guide to corydalis.
Season of interest: Spring to summer
Summer season
Himalayan poppy
The delicate Himalayan poppy can be tricky to grow but is such a gorgeous shade of sky blue it is impossible to leave out. They prefer a cool climate and part shade to grow well, so will only grow only in the cooler parts of Britain. With large, sky-blue flowers, Meconopsis (Fertile Blue Group) 'Lingholm' (above) was discovered on the Lingholm estate in the Lake District. It is a longer-lived perennial than other cultivars and grows well from seed. Best sown with freshly gathered seeds in late summer; don’t sow too thickly, as it is notorious for damping off, and overwinter it in a cold frame. T
Season of interest May through June.
Delphinium
Delphiniums come in shades of blue that range from pale baby blue to the deepest indigo. They are eyecatching plants for the back of a border and make stunning cut flowers. Delphinium ‘Cupid’ has short, fat spikes of sky-blue flowers that have been brushed with mauve at the base of the sepals. Being short, it does not need staking and can stand up to wind better than most delphiniums. 1m. RHS H5, USDA 5a-7b.
Season of interest: June-July
Echium vulgare
A strikingly beautiful biennial with bristly, spotted leaves and stems, and bright-blue flower spikes from June to August. Drought resistant and a magnet for bees. 1m. RHS H7, USDA 4a-8b.
Season of interest: June to August
Salvia
There are many salvias to choose from, many of which offer a long flowering period and lots of colour options, but blue is a lively option. Salvia Bullulata 'Pale Form' is a pale-blue almost turquoise form of a rare and variable species from Peru.
Season of interest: Summer to autumn
Veronicastrum
Elegant, hardy and easy to cultivate, veronicastrums offer a long season of interest and are useful to pollinating insects. Veronicastrums can grow to 1-1.8m and their flower spikes give a vertical accent to a border. They will tolerate most soils if they are not too dry, and a wide range of pH. Grow in sun or partial shade .
Season of interest: Summer to autumn
Agapanthus
Agapanthus are versatile perennials for gardens of all sizes and situations, whether you grow them in pots, in the border or as cut flowers. They look good in herbaceous borders and are tolerant of salty winds, so make good coastal plants. They also look good in a jungle-style garden or in an exotic garden. Flowering times for Agapanthus vary by region, but there are early-flower cultivars which bloom from June. They come in a range of blues, from icy blue to deep indigo.
Season of interest: Summer
Hydrangea
Hydrangea comes in many different colours, but blue is one of the loveliest. The flowers of this old cultivar, said to be a mutation of H. macrophylla ‘Joseph Banks’, are soft lilac-blue, and treasured for their distinct in-curved petals.
Season of interest July – September.
Borage
Borage is one of what are known as pioneer plants, those hardy species that are the first to colonise previously damaged ecosystems. It’s an annual plant found in many parts of Europe often growing along grass verges and below bushes, with leaves and stems that are covered with a woolly layer. It self sows easily and is beloved by bees thanks to the flowers that refill rapidly with nectar having been visited by a pollinator. The star-like flowers can be used to garnish drinks and salads.
Season of interest: Summer to autumn.
Hardy geraniums
While these flowers often sit on the border between blue and purple, there are some varieties that are clearly blue. Versatile plants that cope well with being chopped back and are generally very adaptable. Pictured here is Geranium 'Orion', with luminous lavender-blue flowers (said to be named after the most luminous constellation in the sky) that are 5cm wide, with darker violet veins, and cover the plant in June and then again in August. It is a large hardy geranium that looks good in the middle of a border and can be used as a ground cover plant. Here's everything you need to know about hardy geraniums.
Season of interest: Summer to autumn
Autumn season
Amsonia
This handsome border perennial looks beautiful when its first shoots emerge in late spring, almost like purple asparagus. These quickly develop into erect, leafy stems with willow-like foliage supporting abundant clusters of star-shaped, sky-blue flowers with white throats. It will flower for five to six weeks and is a good, tidy, fresh-green foliage plant throughout the season before turning golden-yellow in autumn. It also has good winter structure.
Season of interest: Flowers May to June; autumn colour in October and November.
Symphyotrichum 'Little Carlow'
Superb Symphyotrichum cordifolium hybrid with heart-shaped lower foliage. The relatively large 25mm daisies are an intense lavender-blue with yellow centres, held in generous sprays from late September. Will tolerate light shade. 1.2m. AGM. RHS H7, USDA 4a-8b.
Read our full profile on growing asters
Season of interest: Autumn