There’s a special kind of magic associated with the color blue in the garden. True blue is one of the rarest and most sought-after hues in the plant world, evoking feelings of calm, serenity, and endless summer skies.
Planting blue annual flowers is like scattering pieces of the sky throughout your landscape, creating cool, tranquil focal points that draw the eye and soothe the soul.
They provide a refreshing contrast to the hot reds and yellows of summer, adding a touch of elegance and depth to any garden design.
This guide is your personal palette of the most beautiful and reliable blue annuals available.
We will explore twelve stunning varieties that will bring that coveted blue hue to your garden beds, containers, and hanging baskets.
You’ll learn about their unique characteristics, how to care for them, and the best ways to use them to create a cool, calming, and breathtakingly beautiful summer garden.
Get ready to discover the power of blue to transform your outdoor space into a peaceful and enchanting retreat.
Essential Supplies for a Beautiful Blue Garden
To help your blue annuals thrive and show off their true colors, having a few key products on hand will set you up for a season of success. These essentials will help you plant, feed, and maintain your garden for spectacular results.
- {Jobe’s Organics All-Purpose Fertilizer Spikes} by Jobe’s: To produce rich, vibrant blooms, your flowers need consistent nutrition. These organic fertilizer spikes are incredibly easy to use. Simply push them into the soil around your plants at the beginning of the season for a steady, slow release of nutrients that feeds the roots over time.
- {Miracle-Gro Moisture Control Potting Mix} by Miracle-Gro: A high-quality potting mix is the foundation of any great container garden. This mix is a fantastic choice as it’s designed to protect against both over- and under-watering by absorbing excess moisture and releasing it when the plant needs it, which is crucial for happy annuals.
- {Fiskars Ergo Garden Tool Set} by Fiskars: Every gardener needs a durable trowel, transplanter, and cultivator. This ergonomic set from Fiskars is designed to reduce hand fatigue, making the initial planting of your beautiful blue garden a much more comfortable and enjoyable task.
- {Dramm One-Touch Rain Wand} by Dramm: Watering is essential, but a harsh blast of water can damage delicate blooms. This rain wand provides a gentle, shower-like spray that won’t harm flowers or displace soil. The easy-to-use one-touch valve allows for effortless water flow control.
- {Felco F-2 Classic Manual Hand Pruner} by Felco: A sharp, reliable pair of pruners is essential for “deadheading” (removing spent blooms) to encourage a continuous show of flowers. Felco pruners are a lifetime investment, known for their precision, durability, and clean cuts that help keep plants healthy.
- {Sluggo Pet Safe Slug and Snail Killer} by Monterey: The cool, moist conditions that some blue flowers enjoy can also be inviting to slugs and snails. Sluggo is an essential, pet-safe solution that effectively controls these common pests without posing a danger to your pets or local wildlife.
12 Stunning Blue Annual Flowers for Your Garden
Ready to infuse your garden with the calming and elegant beauty of blue? Here are twelve reliable and stunning annuals that will bring a touch of the sky to your outdoor space.
1. Salvia
When it comes to blue annual flowers, salvia is a true star. The annual varieties produce tall, elegant spires of small, densely packed flowers that are magnets for hummingbirds, bees, and butterflies. They add an essential vertical element to garden beds and containers.
- Why You’ll Love Them: The deep, intense indigo-blue of many salvia varieties is simply breathtaking. They are very heat and drought-tolerant once established and bloom continuously throughout the summer, providing a long season of color and pollinator activity.
- Growing Tips: Plant salvia in full sun and well-drained soil. While they are tough, they will bloom more profusely with consistent moisture. Cutting off the main flower spike after it fades will encourage the plant to send up new side shoots with more flowers, extending the bloom time.
- Varieties to Try: Salvia farinacea ‘Victoria Blue’ is a classic and award-winning variety, famous for its deep, true-blue flower spikes. Salvia guaranitica ‘Black and Blue’ is another showstopper, with brilliant cobalt-blue flowers emerging from near-black calyxes, a favorite of hummingbirds.
For a bold, vertical statement and a non-stop pollinator party, blue salvia is an invaluable addition to any sunny garden.
2. Lobelia
For an intense, electric, true-blue color, few plants can compete with annual lobelia. This delicate-looking plant produces a cascade of tiny, brilliant blue flowers, making it a classic “spiller” for containers and hanging baskets.
- Why You’ll Love Them: The vibrant, cobalt-blue color of classic lobelia is unparalleled. It creates a stunning waterfall of color from hanging baskets and window boxes, pairing beautifully with almost any other annual. Its fine texture adds a soft, airy quality to arrangements.
- Growing Tips: Lobelia is a cool-season annual that dislikes intense heat. For the best performance, plant it in a partial sun location, especially one that provides shade during the hottest part of the afternoon. It must have consistently moist soil and will decline quickly if it dries out.
- Varieties to Try: Look for modern, heat-tolerant varieties like the ‘Laguna’ or ‘Techno Heat’ series. These have been specifically bred to continue blooming further into the summer than older types. ‘Laguna Sky Blue’ is a particularly popular and beautiful choice.
For an unforgettable splash of true blue that cascades beautifully, lobelia is a must-have for your cool-season and partial-sun containers.
3. Ageratum (Floss Flower)
Ageratum, commonly known as floss flower, is a charming annual that produces fluffy, button-like clusters of flowers. It’s most famous for its beautiful and unique shade of powder blue, a soft and fuzzy texture that is unlike anything else in the garden.
- Why You’ll Love Them: The soft, fuzzy texture and unique powder-blue color of ageratum make it a wonderful plant for adding textural contrast. It’s a favorite of butterflies, especially Monarchs and Swallowtails. It blooms continuously from late spring until frost.
- Growing Tips: Ageratum performs well in full sun to partial shade. In hotter climates, it appreciates some afternoon shade to help the flowers last longer and prevent the leaves from scorching. Plant it in moist, well-drained soil. Regular deadheading of the spent flower clusters will keep the plant looking tidy and encourage new flushes of bloom.
- Varieties to Try: ‘Blue Hawaii’ is a popular, compact variety with a rich blue-violet color. Taller varieties like ‘Blue Horizon’ are excellent for cutting and adding to bouquets.
For a unique, fuzzy texture and a beautiful shade of soft blue, ageratum is a wonderful and reliable addition to the garden.
4. Browallia (Amethyst Flower)
Browallia is a fantastic but sometimes overlooked blue annual flower that thrives in shady conditions. It produces a cloud of beautiful, star-shaped flowers in brilliant shades of blue and purple, looking much like a shade-loving version of vinca.
- Why You’ll Love Them: The vibrant, true-blue to deep-violet color of many browallia varieties is a rare and valuable asset for the shade garden. It is incredibly heat-tolerant and blooms its heart out all summer long with very little maintenance, as it is self-cleaning.
- Growing Tips: Plant browallia in part to full shade in rich, well-drained soil. It appreciates consistent moisture but is more forgiving of occasional dryness than impatiens. It forms a lovely, mounded-to-trailing habit that is perfect for shady containers and baskets.
- Varieties to Try: The ‘Endless’ series is aptly named for its non-stop blooming power. ‘Endless Illumination’ is a particularly stunning variety with deep, amethyst-blue flowers that seem to glow in the shade.
For a blast of brilliant blue that lasts all summer in your shadiest spots, browallia is an excellent and low-maintenance choice.
5. Petunia
While available in every color, the blue and purple varieties of petunia are particularly rich and beautiful. They offer a classic look and an incredible profusion of blooms that can fill any sunny spot with a cascade of cool color.
- Why You’ll Love Them: Blue petunias are incredibly versatile. They can be planted on their own for a dramatic, monochromatic statement, or used to provide a cool-toned counterpoint to hot pinks and yellows. At dusk, the deep blue and purple blooms take on a velvety, luminous quality.
- Growing Tips: Petunias are sun-worshippers and need at least six hours of direct sun to produce their famous avalanche of blooms. They are heavy feeders, so fertilize them every few weeks with a water-soluble plant food to keep them performing their best.
- Varieties to Try: The ‘Easy Wave Blue’ petunia is a vigorous trailing type, perfect for a massive cascade of color. ‘Supertunia Royal Velvet’ has rich, deep purple-blue flowers that look like velvet. ‘Night Sky’ is a unique variety with deep purple flowers speckled with white, looking like a galaxy.
For reliable flower power and rich, deep cool tones in your sunniest spots, blue petunias are an unbeatable choice.
6. Cornflower (Centaurea cyanus)
Also known as bachelor’s button, the cornflower is a charming, old-fashioned annual prized for its brilliant, true-blue flowers. It has a wild, meadow-like charm and is incredibly easy to grow from seed.
- Why You’ll Love Them: The intense, clear blue of the classic cornflower is one of the truest blues in the flower world. They are fantastic cut flowers and can also be dried for arrangements. They are a favorite of bees and other pollinators.
- Growing Tips: Cornflowers are a cool-season annual. For the best results, sow seeds directly in the garden in early spring or even in the fall in milder climates. They prefer full sun and well-drained soil and will often self-sow, returning year after year.
- The Look: Cornflowers have a charming, slightly shaggy appearance that is perfect for a cottage garden or a wildflower meadow planting. Their silvery-green foliage is also attractive.
For an easy-to-grow, true-blue flower with a charming, rustic feel, the cornflower is a classic choice.
7. Evolvulus (Blue Daze)
Evolvulus, commonly known as Blue Daze, is a fantastic trailing annual that produces a profusion of the most perfect, sky-blue, morning glory-like flowers. It is incredibly heat and drought-tolerant, making it a star performer in hot, sunny locations.
- Why You’ll Love Them: The clear, sky-blue color of the flowers is absolutely stunning. It blooms non-stop from spring until frost, with each flower lasting only a day but being quickly replaced by another. It has beautiful, fuzzy, silver-green foliage that provides a lovely contrast.
- Growing Tips: Blue Daze needs full sun to bloom well. It is a fantastic choice for hanging baskets, containers, or as a groundcover in hot, dry areas. It demands well-drained soil and is very drought-tolerant once established.
- The Look: This plant creates a beautiful, low-growing mat or trailing cascade of silvery foliage studded with brilliant sky-blue flowers. It’s a perfect choice for a coastal or Mediterranean-style garden.
For a tough, heat-loving plant with a perfect sky-blue flower, Evolvulus is one of the best blue annual flowers you can find.
8. Pansy & Viola
Pansies and violas are the cheerful faces of the cool seasons, and their blue and purple varieties are particularly beautiful. They can provide that coveted blue color in early spring and late fall when few other plants are blooming.
- Why You’ll Love Them: Many blue violas and pansies have a sweet, pleasant fragrance. By planting them in a location with afternoon shade, you can often extend their bloom season well into the summer. Their edible flowers are also a beautiful garnish for salads and desserts.
- Growing Tips: Plant them in a location that gets morning sun and afternoon shade. They must have consistently moist soil to perform well as temperatures rise. Deadheading the spent blooms will encourage them to keep producing more flowers.
- Varieties to Try: Look for true-blue varieties like ‘Delta True Blue’ pansy or the classic Johnny-jump-up viola with its charming purple and yellow face.
For reliable cool-season color, the charming faces of blue pansies and violas are a garden essential.
9. Swan River Daisy (Brachyscome)
The Swan River daisy is a charming and delicate-looking annual native to Australia. It produces a profusion of small, fine-petaled, daisy-like flowers on a mound of lacy, fern-like foliage.
- Why You’ll Love Them: This plant is tough, heat-tolerant, and blooms non-stop all summer. The blue and lavender varieties are particularly beautiful, creating a soft, airy cloud of cool color. It’s a fantastic filler plant for containers and hanging baskets.
- Growing Tips: Plant Swan River daisy in full sun to light shade in well-drained soil. It is fairly drought-tolerant once established. It does not require deadheading to continue blooming.
- The Look: The fine-textured foliage and delicate flowers create a very soft, romantic look. It’s perfect for adding an airy, graceful touch to mixed containers, where it will weave its way through other plants.
For a delicate, airy, and long-blooming blue daisy, the Swan River daisy is a wonderful and underused choice.
10. Nemophila (Baby Blue Eyes)
Nemophila, affectionately known as baby blue eyes, is a delightful, low-growing, cool-season annual. It produces a carpet of the most charming, cup-shaped flowers in a perfect shade of sky blue, often with a white center.
- Why You’ll Love Them: The innocent, upward-facing flowers are incredibly charming and have an old-fashioned appeal. They are very easy to grow from seed and are perfect for creating a temporary groundcover in the spring.
- Growing Tips: Baby blue eyes thrive in cool, moist conditions. Sow seeds directly in the garden in early spring or in the fall for spring blooms in mild climates. They prefer full sun to partial shade and consistently moist soil. They will fade away as the intense heat of summer arrives.
- The Look: A patch of baby blue eyes looks like a piece of the sky has fallen to the ground. They are perfect for rock gardens, woodland edges, and for underplanting taller spring bulbs like tulips and daffodils.
For a carpet of the most perfect, clear sky-blue in the cool spring garden, baby blue eyes are truly magical.
11. Scaevola (Fan Flower)
Scaevola, or fan flower, is a tough and beautiful trailing annual native to Australia. It gets its name from its unique flowers, which look like a tiny fan with all the petals arranged on one side.
- Why You’ll Love Them: Scaevola is incredibly heat-tolerant, drought-tolerant, and self-cleaning. It’s one of the easiest trailing plants you can grow for a hot, sunny spot. The blue and purple varieties provide a constant stream of cool color all summer long.
- Growing Tips: Plant scaevola in full sun in well-drained soil. It is an excellent choice for hanging baskets and containers, where its trailing habit can be shown off. It is very low-maintenance and requires no deadheading.
- Varieties to Try: The ‘Whirlwind’ series is known for its large flowers and vigorous, well-branched growth. ‘Whirlwind Blue’ is a fantastic performer with beautiful blue-purple flowers.
For a unique flower shape and incredible toughness in the heat, scaevola is a top-tier trailing blue annual.
12. Love-in-a-Mist (Nigella damascena)
Love-in-a-mist is an old-fashioned cottage garden flower with a wonderfully romantic and mysterious quality. It has intricate, jewel-like blue flowers that are surrounded by a “mist” of fine, feathery foliage.
- Why You’ll Love Them: The flowers are incredibly unique and beautiful. After the flower fades, it is followed by an equally attractive, balloon-like seed pod that is fantastic in dried arrangements. It’s very easy to grow from seed and will often self-sow.
- Growing Tips: Love-in-a-mist is a cool-season annual. Sow seeds directly in the garden in full sun in the spring. It is not picky about soil. It has a relatively short bloom time, so it’s a good idea to sow seeds every few weeks for a continuous supply of flowers.
- Varieties to Try: ‘Miss Jekyll Blue’ is the classic variety with beautiful sky-blue flowers. The ‘Persian Jewels’ mix includes shades of blue, pink, and white.
For a unique, romantic, and beautiful cut flower with an interesting seed pod, love-in-a-mist is a charming addition to the garden.
Recommended Product Summary
Here is a quick-glance table of the essential supplies that will help you create a stunning and healthy garden filled with blue annual flowers.
| Product Name | Brand | Use Case |
|---|---|---|
| {Jobe’s Organics Fertilizer Spikes} | Jobe’s | An easy-to-use, organic fertilizer for season-long, slow-release feeding. |
| {Miracle-Gro Moisture Control Potting Mix} | Miracle-Gro | A potting mix that helps prevent over- and under-watering in containers. |
| {Fiskars Ergo Garden Tool Set} | Fiskars | The essential, durable hand tools for planting your garden beds and pots. |
| {Dramm One-Touch Rain Wand} | Dramm | For providing a gentle, thorough watering that is ideal for delicate annuals. |
| {Felco F-2 Classic Hand Pruner} | Felco | A high-quality tool for deadheading to encourage continuous blooms. |
| {Sluggo Pet Safe Slug and Snail Killer} | Monterey | An essential, pet-safe way to control common pests in moister garden areas. |
Bring the Calm and Beauty of Blue to Your Garden
The quest for true blue is one of the most rewarding journeys a gardener can take. These beautiful blue annual flowers offer a full season of cool, tranquil color, transforming your garden into a serene and elegant retreat.
Whether you’re planting a cascading basket of brilliant lobelia or a stately stand of deep blue salvia, these flowers have the power to soothe the soul and delight the eye. So, embrace the magic of blue.
Try a few of these stunning varieties, and get ready to enjoy a garden that is as peaceful and beautiful as a clear summer sky.
