Looking for easy blue flowers to grow in your garden? Blue is the rarest color in the flower world, which makes a blue garden absolutely stunning.
In this guide, we share 11 beautiful and easy blue flowers to grow that will transform any space — whether you have a large backyard, a small patio, or just a sunny windowsill. Our list includes both blue perennial flowers that come back year after year and blue annual flowers that deliver vibrant color all season long.
Why Easy Blue Flowers to Grow Are So Special (And Hard to Find!)
True blue is the rarest color in the flower world, making rare blue flowers a prized addition to any garden. While nature gives us plenty of reds, yellows, and whites, genuinely blue blooms are few and far between (due to the chemistry of anthocyanin pigments) — but there are still plenty of easy blue flowers to grow. That’s exactly what makes a blue flower garden so striking — it immediately catches the eye and stands apart from every other yard on the block.
The good news? You don’t need to be a master gardener to grow stunning blue flowers. Whether you have a sprawling backyard, a small patio, or even just a sunny windowsill garden, there’s a blue bloom that will thrive in your space.
In this guide, I’m sharing my top 10 favorite easy-to-grow blue flowers, complete with growing zones, sun requirements, and tips for getting the most blooms out of each one. Let’s dive in!
1. Hydrangea (Hydrangea macrophylla)
Hydrangeas are the queen of blue flowers, and they’re one of the few plants where you can actually control the bloom color. The secret? Soil acidity. Acidic soil (pH below 6.0) produces those gorgeous blue blooms, while alkaline soil turns them pink.
Growing Details:
- USDA Zones: 5–9
- Sun: Partial shade to full sun (morning sun, afternoon shade is ideal)
- Soil: Moist, well-drained, acidic soil for blue blooms
- Height: 3–6 feet
- Bloom Time: June through September
- Indoor/Outdoor: Primarily outdoor; dwarf varieties work in large containers
Pro Tip: Add aluminum sulfate to your soil to lower the pH and intensify the blue color.
2. Forget-Me-Not (Myosotis sylvatica)
If you’re looking for blue flowers for shade, Forget-Me-Nots are your answer.
These tiny, delicate blue flowers are absolutely magical when they carpet a shaded garden bed. Forget-me-nots self-seed so freely that once you plant them, they come back year after year without any effort.
Growing Details:
- USDA Zones: 3–8
- Sun: Partial shade to full shade
- Soil: Moist, well-drained
- Height: 6–12 inches
- Bloom Time: April through June
- Indoor/Outdoor: Both — wonderful in containers and window boxes
Pro Tip: Plant forget-me-nots alongside spring bulbs like tulips and daffodils. As the bulb foliage dies back, forget-me-nots fill in beautifully.
3. Morning Glory (Ipomoea tricolor ‘Heavenly Blue’)
If you want a fast-growing blue flower that creates a dramatic display, morning glories are your answer. The ‘Heavenly Blue’ variety produces incredible sky-blue trumpet flowers that open fresh every morning.
Growing Details:
- USDA Zones: 2–11 (grown as annual)
- Sun: Full sun (6+ hours)
- Soil: Average, well-drained
- Height: 8–12 feet (climbing vine)
- Bloom Time: July through first frost
- Indoor/Outdoor: Outdoor only — needs a trellis or structure to climb
Pro Tip: Nick or soak the seeds overnight before planting to speed up germination.
4. Cornflower / Bachelor’s Button (Centaurea cyanus)
Cornflowers are one of the few flowers that produce a true, pure blue. They’re incredibly low-maintenance annuals that thrive in poor soil and drought conditions.
Growing Details:
- USDA Zones: 2–11 (annual)
- Sun: Full sun
- Soil: Average to poor, well-drained
- Height: 1–3 feet
- Bloom Time: Late spring through summer
- Indoor/Outdoor: Primarily outdoor; great for cutting gardens
Pro Tip: Cornflowers are edible! Add the petals to salads or freeze them in ice cubes.
5. Lobelia (Lobelia erinus)
Lobelia is the perfect blue flower for containers, hanging baskets, and border edges. Cascading varieties spill beautifully over pot edges, creating a waterfall of tiny blue flowers.
Growing Details:
- USDA Zones: 10–11 as perennial; grown as annual elsewhere
- Sun: Full sun to partial shade
- Soil: Rich, moist, well-drained
- Height: 4–9 inches
- Bloom Time: Spring through fall
- Indoor/Outdoor: Both — excellent for indoor containers near bright windows
Pro Tip: If lobelia stops blooming in midsummer heat, cut it back by half. It’ll bounce back when temperatures cool.
6. Delphinium (Delphinium elatum)
Delphiniums are the showstoppers of the blue flower world. Their tall, dramatic flower spikes can reach 4–6 feet packed with stunning blue blooms. They’re the backbone of classic English cottage gardens.
Growing Details:
- USDA Zones: 3–7
- Sun: Full sun (at least 6 hours)
- Soil: Rich, moist, well-drained, slightly alkaline
- Height: 2–6 feet
- Bloom Time: Early to mid-summer
- Indoor/Outdoor: Outdoor only — perfect for back-of-border plantings
Pro Tip: Stake delphiniums early! Those tall flower spikes are top-heavy and will snap in wind or rain.
7. Blue Star Creeper (Isotoma fluviatilis)
Blue star creeper forms a dense, low mat of tiny star-shaped blue flowers that’s perfect between stepping stones, along pathways, or as a lawn alternative.
Growing Details:
- USDA Zones: 5–9
- Sun: Full sun to partial shade
- Soil: Moist, well-drained
- Height: 1–3 inches
- Bloom Time: Late spring through summer
- Indoor/Outdoor: Primarily outdoor; excellent ground cover
Pro Tip: Blue star creeper tolerates mild foot traffic — great between pavers where grass won’t grow.
8. Salvia (Salvia farinacea ‘Victoria Blue’)
Blue salvia blooms continuously from late spring through frost, attracts hummingbirds and butterflies, and is incredibly drought-tolerant once established.
Growing Details:
- USDA Zones: 8–10 as perennial; annual in cooler zones
- Sun: Full sun
- Soil: Well-drained, average
- Height: 18–24 inches
- Bloom Time: Late spring through first frost
- Indoor/Outdoor: Outdoor — great for borders and pollinator gardens
Pro Tip: Deadhead spent flower spikes regularly for continuous blooms from May through November.
9. Grape Hyacinth (Muscari armeniacum)
Grape hyacinths are one of the first blue flowers to bloom in spring. These charming bulbs produce clusters of tiny, grape-like blue flowers that multiply freely.
Growing Details:
- USDA Zones: 3–9
- Sun: Full sun to partial shade
- Soil: Well-drained, average
- Height: 6–8 inches
- Bloom Time: Early to mid-spring (March–April)
- Indoor/Outdoor: Both — bulbs can be forced indoors for winter blooms
Pro Tip: Plant grape hyacinth bulbs in large drifts of 25+ for the best visual impact.
10. Plumbago (Plumbago auriculata)
Plumbago produces clusters of sky-blue flowers nonstop from spring through fall. In warm climates, it’s an evergreen shrub. This is also one of the best blue flowers for containers. In cooler zones, it makes a spectacular container plant.
Growing Details:
- USDA Zones: 9–11 (container plant in cooler zones)
- Sun: Full sun to light shade
- Soil: Well-drained, fertile
- Height: 6–10 feet (shrub/vine); smaller in containers
- Bloom Time: Spring through fall
- Indoor/Outdoor: Both — grows beautifully in containers moved indoors in winter
Pro Tip: Plumbago can be trained on a trellis or as ground cover. In zones 9–11 it makes an incredible flowering hedge.
11. Butterfly Bush (Buddleja davidii)
Butterfly Bush is a stunning blue perennial flower that comes back year after year, producing long, cone-shaped flower clusters that are irresistible to butterflies and hummingbirds. The ‘Blue Chip’ and ‘Pugster Blue’ varieties offer gorgeous blue-purple blooms and are more compact than older cultivars. This is one of the best blue flowers for full sun and makes an outstanding focal point in any garden.
Growing Details:
- USDA Zones: 5-9
- Sun: Full sun (6+ hours)
- Soil: Average, well-drained
- Height: 3-6 feet (dwarf varieties 2-3 feet)
- Bloom Time: Summer through fall
- Indoor/Outdoor: Outdoor only — needs room to spread
Pro Tip: Deadhead spent blooms regularly to encourage continuous flowering all season long. In colder zones, cut back to 12 inches in late winter for vigorous spring regrowth.
Below is a handy chart summarizing all 11 easy blue flowers to grow at a glance.
Quick Reference: 11 Easy Blue Flowers to Grow Chart
| Flower | Zones | Sun | Height | Bloom Time | Best For |
|---|---|---|---|---|---|
| Hydrangea | 5–9 | Part shade | 3–6 ft | Jun–Sep | Borders, focal point |
| Forget-Me-Not | 3–8 | Part shade | 6–12 in | Apr–Jun | Shade gardens, containers |
| Morning Glory | 2–11 | Full sun | 8–12 ft | Jul–frost | Fences, trellises |
| Cornflower | 2–11 | Full sun | 1–3 ft | Late spring–summer | Cutting gardens, meadows |
| Lobelia | Annual | Sun/part shade | 4–9 in | Spring–fall | Containers, baskets |
| Delphinium | 3–7 | Full sun | 2–6 ft | Early summer | Back of border |
| Blue Star Creeper | 5–9 | Sun/part shade | 1–3 in | Late spring–summer | Ground cover, pathways |
| Salvia | 8–10 | Full sun | 18–24 in | Late spring–frost | Borders, pollinator gardens |
| Grape Hyacinth | 3–9 | Sun/part shade | 6–8 in | Mar–Apr | Naturalizing, rock gardens |
| Plumbago | 9–11 | Full sun | 6–10 ft | Spring–fall | Hedges, containers |
| Butterfly Bush | 5-9 | Full sun | 3-6 ft | Summer-fall | Borders, focal point |
Tips for Growing a Stunning Blue Flower Garden
One of the best strategies is to mix blue perennial flowers like Hydrangeas, Delphiniums, and Butterfly Bushes with blue annual flowers like Lobelia and Cornflowers for continuous color from spring through fall.
Once you’ve chosen your favorite easy blue flowers to grow, here are some design tips to make the most of them. Whether you need blue flowers for shade under trees or blue flowers for full sun in open beds, there’s a perfect option for every spot:
Now that you know which easy blue flowers to grow, here are a few design tips to make the most of them:
When arranging your easy blue flowers to grow, pair blue with yellow or orange — complementary colors make blue flowers pop even more. Try blue salvia next to yellow marigolds, or blue hydrangeas near orange daylilies.
Use blue flowers to create depth — blue recedes visually, so planting blue flowers at the back of a border makes your garden appear larger and deeper.
Layer your bloom times — by choosing a mix from this list, you can have blue flowers blooming from early spring (grape hyacinths) through late fall (salvia and plumbago).
Don’t forget containers — if you have limited space, lobelia, forget-me-nots, and plumbago all thrive in pots.
Recommended Products to Get Started
Here are some products that will help you get your blue flower garden growing:
- Endless Summer Hydrangea Soil Acidifier — Essential for turning hydrangeas blue.
- Burpee ‘Heavenly Blue’ Morning Glory Seeds — The classic sky-blue morning glory variety.
- Muscari Grape Hyacinth Bulbs (50 pack) — Buy in bulk for the best spring display.
- Delphinium ‘Blue Bird’ Seeds — Stunning tall spikes of pure blue.
- Espoma Organic Soil Acidifier — Great for acid-loving blue flowers.
- Bamboo Garden Stakes (25-pack) — Perfect for staking delphiniums.
- Self-Watering Hanging Basket — Ideal for cascading lobelia.
- Miracle-Gro Bloom Booster Flower Food — Promotes more blooms on all flowering plants.
Final Thoughts
These easy blue flowers to grow prove that while rare blue flowers might seem hard to find in nature, but with the right plant choices, you can create a garden filled with stunning blue blooms from early spring through late fall.
The 11 flowers on this list are all beginner-friendly, widely available, and proven performers.
Start with just two or three varieties from different bloom-time categories, and you’ll be amazed at how much a pop of blue transforms your entire garden. With so many easy blue flowers to grow, you’re sure to find the perfect match for your garden. Happy planting!
Which blue flower are you most excited to try? Drop a comment below and let me know!