14 Blue Flowers You Can Plant From Seed
True blue flowers are surprisingly rare in gardens, but growing from seed opens up varieties you'll rarely find as transplants. These blues range from deep navy to soft sky blue, offering colors that make other garden shades look better by contrast.
Contents
Blue flowers are weirdly hard to find at garden centers. Most “blue” plants sold as transplants are actually purple, lavender, or that weird purple-pink that’s tough to coordinate with. Real blue that looks like sky or ocean exists mainly in varieties you have to grow from seed.
This is partly because true blue pigments are genetically uncommon in plants. It’s also because many of the best blue-flowering varieties don’t ship well as transplants or aren’t commercially popular enough for mass production. Seed companies carry them, but you won’t usually see them at big box stores.
Growing these flowers from seed gives you access to impressive colors in your garden design. Blue calms down hot color schemes, makes whites look cleaner, and provides contrast that yellow and orange flowers look better with. It’s worth the extra effort of starting these stunning flowers from seed.
‘Mammoth Navy Blue’ Sweet Pea
These deep blue flowers on quickly climbing vines bring a beautiful color to vertical spaces. The fragrance is also incredible, sweet and strong enough to perfume entire patios when plants are in full bloom. If you’ve never smelled a sweet pea in full bloom, I promise you’re missing out on one of gardening’s greatest sensory experiences.
Sweet peas are cool-season annuals that perform best when planted in late winter or early spring. In warm climates, you can plant in fall for winter blooms. They hate heat and will decline once temperatures consistently hit the 80s. Plant them about an inch deep and provide support immediately since they start climbing from the moment they germinate.
‘Rocky Mountain Blue’ Penstemon
This native penstemon produces tubular blue flowers that hummingbirds absolutely love. The plants bloom from late spring through early summer.
Seeds need cold stratification to germinate reliably, so either sow them in fall or give them a couple of weeks in the refrigerator before spring planting. Surface sow since the seeds need light to germinate. Once established, these are incredibly drought-tolerant and handle poor soil without complaint.
‘Shades of Blue’ Larkspur
If you want dramatic vertical accents in cottage gardens, these are the blue flowers to choose. Larkspur looks similar to delphinium but is much easier to grow from seed (and more heat-tolerant). These can reach up to four feet tall, creating those dreamy cottage garden scenes we all know and love.
Direct sow larkspur in fall or very early spring, as they germinate best in cool soil and won’t perform well with late spring planting. They look best when planted in large groups for a big impact.
‘Miss Jekyll Blend’ Love-in-a-Mist
Delicate flowers surrounded by feathery foliage give love-in-a-mist an almost ethereal appearance. The common name comes from the way flowers appear to float in a mist of thread-like foliage (it’s weirdly accurate once you see it). The seed pods are nearly as ornamental as the flowers and dry beautifully for arrangements.
Direct sow in early spring or fall since these don’t transplant well. The seeds germinate quickly in cool soil, usually within 10-14 days. These are short-lived flowers that bloom for about a month, then set seed and decline. Succession plant every few weeks for continuous blooms, or just enjoy the one flush and save seeds for next year.
‘Blue Boy’ Bachelor’s Button
This old-fashioned annual produces bright blue flowers that are perfect for cutting gardens. The flowers last well in arrangements and keep producing if you cut regularly.
Bachelor’s buttons are among the easiest flowers to grow from seed. Just scatter them where you want them in fall or early spring and rake lightly. They’ll germinate without any special treatment and bloom within weeks. The plants tolerate poor soil, drought, and general neglect better than most annuals.
‘Rocky Mountain Blue’ Columbine
This native columbine with true blue flowers and delicate spurred petals attracts early pollinators. The spurred petals evolved to accommodate long-tongued pollinators, which is why bumblebees go absolutely wild for them. The plants prefer partial shade and handle woodland conditions where other flowers might struggle.
Columbine often takes a full year to bloom from seed, so don’t expect flowers the first season. The ferny foliage is attractive on its own though, and once established, the plants perform well without much attention.
‘Blue and Breezy’ Flax
These sky blue flowers create an airy, naturalistic look in borders. The flowers are so delicate that they’ll sway in the slightest breeze, creating constant movement in the garden (and pairing well with ornamental grasses). Each flower lasts just one day, but plants produce so many buds that there’s always something blooming.
Seeds germinate quickly in spring, usually within a week if the soil is warm enough. These are low-maintenance plants that don’t need deadheading, fertilizing, or much attention beyond occasional watering during drought. The flowers close at night and on cloudy days, so plant them where they’ll get good sun exposure.
‘Spring and Summer’ Forget-Me-Not
Forget-me-nots are biennials that bloom in their second year. Sow seeds in late summer or fall for masses of flowers the following spring.
This species can spread aggressively in moist, shady conditions. Plant them where you don’t mind volunteers appearing, or be prepared to remove seedlings regularly to keep them contained.
‘Crystal Palace’ Lobelia
These deep blue flowers have a slight purple undertone that looks stunning paired with purple or even white blooms. The mounding habit reaches a compact six inches tall and spreads to about 12 inches. Despite the compact size, each plant can produce hundreds of tiny flowers over the season.
Start lobelia seeds indoors around 10 weeks before your last frost date. Keep soil consistently moist until germination. These prefer cooler weather and partial shade, especially in hot climates. They’ll bloom continuously from spring through fall in ideal conditions, but may pause during the hottest months.
‘Cambridge Blue’ Lobelia
Soft powder blue flowers offer a gentler alternative to the intense hue of ‘Crystal Palace’. The trailing habit makes this variety perfect for hanging baskets or spilling over container edges.
Luckily, growing instructions are the same as ‘Crystal Palace’ and just as easy. Start indoors, surface sow, and keep moist. The main difference is the growth habit and slightly softer color. You can also plant both types together, as the different growth habits complement each other without competing.
‘Blue Victory’ Salvia
Salvias are excellent pollinator plants, and if you want blue flowers, ‘Blue Victory’ is the cultivar to choose. Spikes of true blue flowers attract butterflies and hummingbirds from midsummer through frost. This variety reaches about 18 inches tall and works well in both containers and borders.
Start seeds indoors 8-10 weeks before the last frost date. Surface sow and keep warm for best germination. The seeds can be slow and erratic to germinate, so don’t give up if nothing happens for a few weeks.
‘Flying Saucer’ Morning Glory
When you grow this morning glory variety, you’ll get huge blue and white striped flowers that open in the morning and close by afternoon. Each vine can produce dozens of blooms daily once established, creating spectacular displays on fences or arbors.
No two flowers are exactly alike. The blue and white striping varies randomly, making each bloom slightly unique.
Morning glories grow aggressively. And sometimes too aggressively. Plant them where you don’t mind vigorous growth, and be aware that they can become weedy in warm climates with long growing seasons.
‘Tweedia’ Milkweed
These unique powder blue flowers look nothing like typical milkweed blooms you may recognize. The star-shaped flowers appear in clusters and support various butterfly species throughout the season.
This milkweed is a tender perennial that’s usually grown as an annual in most climates. In zones 9-11, it may overwinter and return for multiple years. You can also grow in large containers to provide some winter protection.
California Bluebells
These California natives perform best in areas with mild summers and can struggle in hot, humid climates. They produce delicate bell-shaped blue flowers in cooler weather.
These are short-lived plants that bloom for several weeks, then decline as temperatures rise. They’re perfect for early spring color in areas where summers get hot, or for longer blooming in coastal areas with cool summers.
