How to Grow and Care for California Lilac

California lilac (Ceanothus) is a flowering plant in the Rhamnaceae (buckthorn) family that is native to North America, particularly California. It is also known by the names mountain lilac, soapbush, buckbrush, blue blossom, and wild lilac. There are a number of cultivars within this genus of plant, some of which grow as evergreen shrubs, others as deciduous trees, and others as clumping, floral ground cover.

These plants typically bloom deep blue flowers (but sometimes are purple or white) with green leaves during the late spring and early summer. California lilacs have a strong fragrance that is known to attract birds, beneficial insects, and pollinators like hummingbirds.

There are many cultivars of California lilac that grow in different sizes with unique flower colors suiting a variety of different landscapes or home gardens. Many of these California native plants are used as ground cover and bring vibrant colors to gardens.

1. 1. Ceanothus ‘Victoria’: Victoria California lilac is a hardy evergreen shrub that grows clusters of vivid indigo blue flowers.
2. 2. Ceanothus ‘Pershore Zanzibar’: This variety of California lilac is an evergreen shrub that blooms in light purple flower clumps. Pershore Zanzibar is known for its bright variegated green leaves that have a dark green center and a light green border.
3. 3. Ceanothus ‘Trewithen Blue’: This evergreen shrub grows deep purple flowers that have showy yellow stamens. It is also known for its glossy leaves.
4. 4. Ceanothus 'Concha’: This clumping shrub is one of the earliest varieties of Ceanothus that has flower clusters that are a very deep blue.
5. 5. Ceanothus arboreus: Though this variety of California lilac is technically a shrub, it grows to the height of a tree, to heights up to thirty feet.
6. 6. Ceanothus ‘Ray Hartman’: This variety of California lilac is more of a small tree than a shrub. It is a hybrid of Ceanothus arboreus and Ceanothus griseus that can grow up to twenty feet tall.
7. 7. Ceanothus 'Dark Star’: Dark star is a lilac shrub that grows smaller clusters of cobalt flowers with yellow stamens that give its flowers the appearance of stars.
8. 8. Ceanothus thyrsiflorus var. repens: This variety of Ceanothus is a creeping variety of evergreen shrub that bears robust blooms of blue flowers.
9. 9. Ceanothus x delileanus ‘Gloire de Versailles’: This low-growing rounded shrub variety with blue flowers and clusters of red berries known for attracting butterflies.
10. 10. Ceanothus ‘Julia Phelps’: Julia Phelps is a very drought tolerant variety of California lilac that has small leaves and vibrant blue blossoms.

Most varieties of California lilac will thrive in USDA hardiness zones 8 through 10 and they are generally very low maintenance plants. They are best grown from softwood cuttings. Follow this guide to grow California lilacs in your own home garden.

1. 1. Obtain a softwood cutting. Take a softwood cutting from an established California lilac bush. Make sure that your cutting is about four to six inches in length, and remove all leaves from the lowest two inches of your branch.
2. 2. Prepare a tray. California lilacs generally prefer well-draining soil not that isn’t too rich in organic matter. Prepare an indoor potting tray with this type of soil.
3. 3. Plant your cutting. Dip the bottom inch of your softwood cutting in rooting hormone and plant it in your potting tray. Tamp the soil down to make sure that your cutting can stand upright. Water your cutting immediately, but do not make the soil too moist. Cover the tray with a plastic bag to create a humid environment, and poke some holes in the bag for proper air circulation.
4. 4. Transplant your cutting. Over the next few months, check on the rooting progress of your lilac. Once you can tug on the plant with a little bit of resistance, it is ready to be planted in its permanent outdoor spot or indoors in a pot. Wherever you decide to plant your cutting, keep in mind that these plants thrive in a location that gets full sun, although they will also tolerate partial shade.

California lilac plants are low-maintenance, but there are a few things you can do to set your plants up for success.

1. 1. Give your plants the right amount of light. California lilacs generally perform best in full sun, but they will also tolerate a few hours of shade.
2. 2. Mind your watering schedule. Water your plant liberally in its first year of growth, but you can scale back watering to once or twice a month once it’s established.
3. 3. Prune your plant. Light pruning is fine for ceanothus plants to promote new growth or to keep them overtaking a garden, but pruning isn’t necessary.

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