Lilac vs. Victorian Lilac

The common lilac (Syringa vulgaris Spp.) and Victorian lilac, also known as "Victoria" California lilac (Ceanothus thyrsiflorus "Victoria") are from two unrelated plant families. The common lilac is from the Oleaceae plant family and the California lilac (Ceanothus Spp.) is from the Rhamnaceae family. The syringa and ceanothus species are only similar in bloom type. The common lilac and its cultivars are deciduous shrubs suitable for gardens in U. S. Department of Agriculture plant hardiness zones 3 through 7, while the California lilac is evergreen and has a more limited range in USDA plant hardiness zones 8 through 10.

The common lilac is a native of Europe. Its abundant blooms and intoxicating scent was so loved by the early North American settlers, they carried it with them across the ocean. The common lilac has now become part of the natural landscape. By the 19th century, breeding programs brought more refined cultivars of the common lilac: the French lilacs, such as "Henri Robert" lilac (Syringa vulgaris "Henri Robert"). Its blue-purple blooms closely resemble those of the California lilac. "Krasavitsa Moskvy" (Syringa vulgaris "Krasavitsa Moskvy") has sprays of pale pink blooms. Both grow to 12 feet and are hardy in UDSA plant hardiness zones 3 through 7. Other lilacs in the oleaceae family include the later blooming "Miss Kim" Korean Lilac (Syringa patula "Miss Kim") with its lavender-blue blooms, and the highly scented Chinese native, Syringa pubescens. Both are hardy in USDA zones 3 through 7.

Lilacs make take up to 5 years to bloom after transplanting them in your garden, but they can thrive for more than a century offering blooming color each spring for future generations. Syringa species and cultivars grow best in full sun in ordinary garden soil. They like moist well-draining soils. Remove the spent flowers directly after they've bloomed to encourage more flower buds for the following spring. Rejuvenate the shrub every few years by removing any dead, weak or old stems. This will keep the lilac healthy and vigorous.

"Victoria" California lilac has deep blue blooms in late spring with thick evergreen foliage. It's a vigorous ceanothus cultivar growing to 9 feet. It is drought-tolerant, but it does needs moist soil after it's transplanted. Once established, you can water less often. "Victoria" are vigorous shrubs, and can be used as stand-alone specimens or as a striking hedge and barrier against coastal winds. It takes well to shearing. "Victoria" California lilac is the most popular ceanothus grown in the Pacific Northwest part of the country.

Like the common lilac "Victoria" California lilac needs well-drained ordinary garden soil and only needs regular watering during the first growing season. The roots don't hold nitrogen, so it will grow in ordinary or poor garden soil with no amendments. It offers a good show, blooming from late spring through summer, so it's best to prune, shear and shape the shrub in early spring. "Victoria" will grow in sun or partial shade.