Here are five dependable, beautiful perennials that actually do have blue flowers. All would be excellent additions to any West Coast garden, and several are hardy through zone 3.
California Lilac (Ceanothus thyrsiflorus). This attractive, evergreen, bushy shrub grows from 10 to 20 feet wide and 4 to 20 feet tall, and can be trained to grow as a small tree. It has wonderfully glossy foliage and in early summer disappears beneath clusters of small blue flowers. It prefers full sun, but will grow in any average soil, is drought tolerant, and so hardy that it's often planted along roadways. These shrubs are bee and butterfly magnets, and make great hedges or windbreaks. My pick is C. thyrsiflorus 'Victoria', which grows about 9 feet tall and spreads to 12 feet wide; it has glorious powder blue flowers.
Bugle plant (Ajuga reptans) is one of my spring-flowering favourites. Not only does it bear spikes of deep blue flowers, but so many of its varieties have such beautiful foliage. 'Burgundy Glow' has foliage variegated green, white, and pink, while 'Bronze Beauty' has, as you would guess, foliage of an attractive bronzy colour. Ajuga is a groundcover that grows about 4 inches tall; while it spreads well, you'll find that it's not as invasive as a lot of groundcovers. And in addition, it's a very tolerant perennial, growing in sun or partial shade, in any soil conditions as well as the soil is well-drained, and needing no maintenance to speak of. And it's hardy zones 3 through 9. My only quarrel with it has been that it's not as robust as some groundcovers and seems to need protection from being overrun by more rampant growers such as Creeping Jenny or Sweet Woodruff.
Lungwort (Pulmonaria) is a must for any shady West Coast garden. These mound-shaped perennials have long hairy leaves, usually spotted, topped in spring with flower stalks bearing clustered cymes of small flowers. With many varieties, the flowers are pink in bud and then open blue, making for an especially attractive display. And lungworts bloom for a long time; mine this year bloomed from the end of February through the end of May. You can't ask for more of a plant than that. I love these so much, I even wrote an entire article about them (
