Blue flowers are a favorite for many gardeners, and for many pollinators, including bees, who see blues and purples better than most other colors. Here are five of our favorite blue flowers that bloom in spring—some at an early time when little else is available to pollinators. In good growing conditions, all of these species will gently spread to form sweeps or splashes that suggest a waterway when the plants bloom.
1. Narrowleaf blue-eyed grass (Sisyrinchium angustifolium)
Not really a grass but a narrow-leaved member of the iris family (Iridaceae), blue-eyed grass shines with tiny gold-centered light blue flowers from spring into early summer. The flowers feed sweat bees, bumblebees and others. This herbaceous perennial can be difficult to tell apart from neighboring grasses when it’s out of bloom. The foliage reaches 12 to 18 inches tall, while the flowering stems add another 6 inches.
Origins: This species is native to moist meadows, fields, open woods, freshwater shores and wetland edges throughout much of the eastern half of North America.
Growing notes: Narrowleaf blue-eyed grass needs regular moisture but its soil should be freely draining. Rich soil can result in floppy growth; this plant looks its best in soil with poor to average fertility. It will grow well in full sun, part shade or dappled shade, but the bloom will be heaviest with more sun. This perennial can be short-lived, but in good conditions it will reseed, and it clumps can be divided every two to three years to rejuvenate the planting. For larger flowers on a more compact plant, look for the cultivar ‘Lucerne’. USDA Zones 4–9.
2. Desert bluebells (Phacelia campanularia)
This is an annual plant hailing from harsh locales such as Joshua Tree National Park, where they make vivid pools of bloom after spring rains. Sturdy red stems rise up in spring to support large, upward-facing, blue flowers with prominent yellow anthers. The toothed foliage is nearly round in shape and minty green with dark veins, forming a mound to about a foot tall and wide.
Origins: Desert bluebells hail from Southern California, specifically the Mojave and Sonoran desert areas.
Growing notes: Site desert bluebells in full sun and loose, sandy or gravelly soil. It is highly drought tolerant but also adaptable outside of xeric landscapes. This plant can be easily grown from seed. In warm regions, sow the seed in late summer or fall; in cold climates wait until after the last spring frost. The flowers feed bumblebees. Desert bluebells can self-sow to create a recurring colony. Annual.
3. Woodland phlox (Phlox divaricata)
Fragrant, purple-blue pinwheels cover the creeping stems of woodland phlox in spring. This North American phlox slowly spreads by rooting where its stems touch the ground. A shade lover, it reaches about 12 inches tall, with a looser habit than sun-loving creeping, or moss, phlox (P. subulata). Its flowers draw butterflies with their nectar.
Origins: This phlox occurs naturally in woods throughout the Northeast, Mid-Atlantic and Midwest United States, into the Upper South.
Growing notes: Woodland phlox thrives in part to full shade and moist, rich soil. For best growth, do not allow the soil to dry completely, and top dress with compost each spring to bolster drainage and fertility. It can decline a bit in the summer, and the stems are not dense enough to crowd out weeds, but these details are easily mitigated by combining woodland phlox with shade perennials that shine through summer. USDA Zones 3–8.
4. Dwarf crested iris (Iris cristata)
Short-stemmed iris flowers appear amid this perennial’s six-inch sword-like leaves in spring, to the delight of bees, butterflies, hummingbirds and gardeners alike. It’s a woodland plant but it adapts to sunnier sites and it tolerates dry soils. It spreads by sending short runners across the soil, but it is not considered aggressive.
Origins: Iris cristata is native to rocky, wooded slopes and stream banks of the Mid-Atlantic, South and Lower Midwest states.
Growing notes: This petite iris grows best in partial or full shade, although it will cope with full sun if it is provided regular moisture. It’s easy to propagate by division; this should occur after flowering. Alternatively, make more dwarf crested iris by severing the running stems with a spade and prying the separated plants up for transplanting. Zones 4–8.
5. Great camas (Camassia leichtlinii)
This bulb is unique for its tolerance of damp soil, even in winter. Great camas makes a substantial clump of grassy foliage in spring, with two-foot spikes of starry, pale blue flowers appearing toward early summer. It will expand by offsets that sprout from the original bulb or seed that drops at the base of the plant.
Origins: Great camas is native to moist slopes and meadows from British Columbia south through California.
Growing notes: Plant camassia bulbs in fall. Full sun provokes the best habit and flowering, although this plant will perform in part shade. Keep the soil moisture consistent while great camas is flowering. Thereafter it prefers a summer dry spell, although it won’t suffer in moist soil, unlike tulips and other spring bulbs. Zones 5–9.
Image credits: Blue-eyed grass by The Marmot/CC BY 2.0; Desert bluebells by Joshua Tree National Park/Public Domain; Woodland phlox by Joshua Mayer/CC BY-SA 2.0; Dwarf crested iris by OakleyOriginals/CC BY 2.0; Great camas by Dr. Alexey Yakovlev/CC BY-SA 2.0