A garden filled with lavender and blue flowers can feel like a breath of fresh air on a hot day. These colors soften harsh sunlight and bring a sense of calm to outdoor spaces. Many cool-toned blooms also thrive in warm climates, offering beauty and comfort during the hottest months. From tall spikes to trailing groundcovers, these plants suit a variety of garden styles. Whether planting a new bed or refreshing a border, these blooms help create a cooler, more relaxing garden. Here are some of the best choices to get you started.
1. Lavender (Lavandula angustifolia)
Lavender is one of the best plants for adding a cool, calming feel to your garden. Its soft purple blooms and silvery-green leaves reflect sunlight, helping to lower the garden's visual temperature. Lavender also releases a gentle scent that can make time outdoors feel more relaxing. It thrives in full sun and well-drained soil, making it a good fit for dry, warm areas. This plant is also a pollinator favorite, attracting bees and butterflies.
2. Russian Sage (Perovskia atriplicifolia)
Russian Sage grows tall and airy, with silvery stems and small lavender-blue flowers. Its open shape and soft colors create a breezy look that cools the garden visually. This drought-tolerant perennial loves hot, sunny spots and poor soil, which makes it easy to grow once established. Russian Sage blooms for a long time, often from summer into fall, keeping your garden looking fresh. Its aromatic leaves also resist deer and pests.
3. Salvia 'Victoria Blue'
Salvia 'Victoria Blue' produces dense spikes of deep blue flowers that can last through much of the growing season. The bright blooms stand out against green foliage, giving your garden a crisp, cool tone. This salvia variety enjoys full sun and well-drained soil, and it can handle dry conditions. It grows well in borders or containers, adding vertical interest and color. Bees and butterflies often visit the flowers, bringing life to your space.
4. Catmint (Nepeta faassenii)
Catmint is a low-growing perennial with soft blue-lavender blooms and fragrant gray-green leaves. It creates a hazy, cloud-like effect in the garden, which feels soothing and cool. This plant handles heat and drought well, making it ideal for low-maintenance landscapes. It blooms in early summer and often reblooms if trimmed back. Catmint grows in mounds and is great for edging walkways or filling in gaps between larger plants.
5. Delphinium (Delphinium spp.)
Delphiniums bring tall spikes of rich blue and purple flowers to the garden. Their bold, upright shape adds height and elegance, while the deep colors cool down sunny borders. Delphiniums prefer cooler climates and need rich, well-drained soil. They also benefit from staking due to their tall stems. These plants bloom in early to midsummer and make striking backdrops for shorter companions.
6. Bluebell (Hyacinthoides non-scripta)
Bluebells are woodland flowers that bloom in spring with delicate, bell-shaped blue flowers. They grow best in shaded areas with moist, well-drained soil. Bluebells create a peaceful mood, especially when planted in drifts under trees or along shaded paths. Their soft colors and gentle arching shape help tone down warm spots in the garden. Once planted, they often naturalize and return each year.
7. Balloon Flower (Platycodon grandiflorus)
Balloon Flowers are known for their balloon-like buds that open into star-shaped blue or purple blooms. These perennials thrive in full sun to part shade and well-drained soil. The plant stays neat and compact, making it perfect for borders or containers. Balloon Flowers bloom in midsummer and require little care once settled. Their cool-toned petals bring a fresh, crisp look to garden beds.
8. Bachelor’s Button (Centaurea cyanus)
Bachelor’s Buttons are cheerful annuals with bright blue flowers that bloom throughout the summer. They grow easily from seed and do well in sunny spots with average soil. The soft, fringed petals and clear blue color help balance warm colors in the garden. These flowers also attract pollinators and make great cut flowers. Bachelor’s Buttons often reseed themselves and return the next year.
9. Columbine 'Blue Star' (Aquilegia caerulea)
Columbine 'Blue Star' features two-tone flowers with pale blue petals and white centers. It prefers part shade and moist, well-drained soil, especially in hot climates. The flowers have a delicate shape and soft colors that cool down shady garden corners. Columbine blooms in spring and early summer, often attracting hummingbirds. Its airy look makes it a good companion for ferns and hostas.
10. Monkshood (Aconitum napellus)
Monkshood has tall spikes of deep blue-purple flowers that look dramatic yet calming. It grows well in part shade and moist, rich soil. Though beautiful, it is important to note that all parts of the plant are toxic and should be handled with care. Monkshood blooms in late summer or early fall, providing color when other plants start to fade. Its dark foliage and cool blooms make it a standout in shady spots.
11. Anise Hyssop (Agastache foeniculum)
Anise Hyssop has lavender-blue flower spikes and fragrant, licorice-scented leaves. It grows well in sunny, dry conditions and attracts many pollinators. The flowers bloom for weeks in mid to late summer, adding soft color and motion to the garden. Anise Hyssop also works well in herb gardens or mixed borders. Its upright shape and drought tolerance make it a great low-care option.
12. Blue Mistflower (Conoclinium coelestinum)
Blue Mistflower has fuzzy clusters of cool blue flowers that bloom in late summer and fall. This native plant prefers moist, rich soil and can spread quickly by underground stems. It grows well in part sun and adds a natural, meadow-like feel to garden edges. Mistflower is especially helpful for filling in bare spots with soft color. Butterflies love its blooms, making it a wildlife-friendly choice.
13. Lobelia (Lobelia erinus)
Lobelia is a trailing plant that produces masses of small blue or purple flowers. It grows well in containers, hanging baskets, or as a border plant. Lobelia prefers cooler weather and moist, well-drained soil. The bright blue flowers cool down garden displays and pair well with warmer tones. In warm climates, it often performs best in spring and fall.
14. Lithodora diffusa 'Heavenly Blue'
Lithodora 'Heavenly Blue' is a low-growing evergreen with brilliant blue star-shaped flowers. It grows well in full sun with well-drained, slightly acidic soil. This plant is great for rock gardens, edging, or spilling over walls. The intense flower color makes a bold contrast with green surroundings. It blooms mostly in spring but may bloom again in cooler weather.
15. Clematis 'Blue Light' (Clematis hybrid)
Clematis 'Blue Light' is a climbing vine with full, double blooms in shades of light blue to lavender. It needs a sunny spot for its flowers but likes its roots to stay cool and shaded. This vine can grow on trellises, fences, or arbors, adding vertical interest. Clematis prefers rich, well-drained soil and regular watering. The large flowers provide a bold yet soothing accent in garden designs.
16. Brunnera 'Jack Frost' (Brunnera macrophylla)
Brunnera 'Jack Frost' has small, sky-blue flowers that bloom in spring above silver-veined leaves. It thrives in shade and moist, well-drained soil. This plant is ideal for brightening up dark corners of the garden. Its foliage lasts through summer, adding texture even after the flowers fade. Brunnera is low maintenance and deer resistant.
17. Hydrangea macrophylla 'Blue Danube'
Hydrangea 'Blue Danube' offers large clusters of blue flowers that bloom in mid to late summer. The flower color depends on soil pH, so more acidic soil will keep the blooms blue. These shrubs prefer morning sun and afternoon shade with rich, moist soil. Their cool-toned blooms help create a relaxing garden setting. Hydrangeas also make great cut flowers for indoor use.
18. Bluebeard (Caryopteris x clandonensis)
Bluebeard is a small shrub with blue flower clusters that bloom in late summer and early fall. It grows best in full sun and well-drained soil. The aromatic leaves and long-lasting blooms make it popular for borders and butterfly gardens. Bluebeard has a tidy shape and requires little pruning. Its cool colors stand out in the heat of summer.
19. Eryngium (Sea Holly)
Sea Holly has spiky, metallic blue flowers and leaves that bring texture and a cool-toned sparkle to sunny gardens. It thrives in poor, dry soil and full sun, making it great for low-maintenance spaces. Sea Holly blooms in summer and is very drought-tolerant. Its unusual look adds contrast and pairs well with softer plants. It is also long-lasting as a cut flower.
20. Veronica spicata 'Royal Candles'
Veronica 'Royal Candles' has upright spikes of vivid blue flowers that bloom from early to midsummer. This plant is compact and tidy, growing well in sunny beds with good drainage. The rich blue color stays bright for weeks, even during hot weather. It attracts pollinators and adds structure to mixed borders. Veronica is easy to grow and needs little care once established.
21. Grape Hyacinth (Muscari armeniacum)
Grape Hyacinth is a spring-blooming bulb with dense clusters of tiny, bell-shaped blue flowers. It grows in full sun to part shade and prefers well-drained soil. Grape Hyacinths often spread over time, forming natural-looking drifts. Their vivid blue color brings a fresh burst to early gardens. They are also easy to grow and require little maintenance.
22. Iris 'Blue Denim' (Iris germanica)
Iris 'Blue Denim' produces large, ruffled flowers in soft denim blue shades. It thrives in full sun and needs well-drained soil, especially in winter. This bearded iris blooms in late spring and sometimes again in fall. Its sword-like leaves add structure even after flowering. Iris clumps can be divided every few years to keep them healthy.
23. Mountain Bluet (Centaurea montana)
Mountain Bluet is a hardy perennial with fringed blue flowers that bloom in late spring. It grows well in full sun or light shade and prefers average, well-drained soil. The plant has gray-green leaves and forms tidy clumps that spread slowly. Mountain Bluet is easy to grow and adds a wildflower look to cottage or natural-style gardens.
24. Scabiosa 'Butterfly Blue' (Scabiosa columbaria)
Scabiosa 'Butterfly Blue' produces lavender-blue pincushion-like blooms from spring through fall. This plant prefers full sun and well-drained soil. It stays compact and works well in borders or containers. The flowers attract bees and butterflies and are good for cutting. Regular deadheading helps keep it blooming.
25. Blue Flax (Linum perenne)
Blue Flax is a delicate-looking perennial with soft blue flowers that bloom on thin, wiry stems. It grows best in full sun and well-drained soil, even in poor or rocky areas. The flowers open in the morning and often drop by afternoon, giving it a fleeting but charming presence. Blue Flax adds movement and lightness to garden beds or wildflower patches.
A Cooler Garden Starts with Color
Choosing plants with lavender and blue blooms is an easy way to bring a fresh, calming look to your garden. These colors soften harsh sunlight and create a more peaceful space for relaxing or entertaining. Whether you prefer soft pastels or bold blues, a flower here fits your style and climate. Many of these plants are easy to grow and attract pollinators, making your garden both beautiful and lively. With the right mix, you can enjoy a cool and colorful garden from spring through fall.