On one of my walk recently my caught an amazing mass of color in a garden on the side of the street, and an unusual color too, blue-violet. When I searched for it I found out it is Ceanothus or California Lilac as it is commonly called. You can grow them as a free-standing shrub or wall-trained and they will ad an incredible display of color. It flowers in late spring or late summer depending on the species. Ceanothus is easy to grow. Many varieties are evergreen, but there are also deciduous varieties. And also some cultivars are fragrant. Also, they come in a variety of sizes.
Ceanothus is from the Rhamnaceae or Buckthorn family of plants. It is also known as Buckbrush, SoapBush, or California Lilac. It is native to North America. Most shrubs grow from 50cm to 3m or 2 or 10ft. However, some varieties can be considered a small tree growing to 6m or 20ft. The leaves are alternate and arranged opposite each other. The flower is white, pink, purple, and blue in clusters. The most common variety is Ceanothus Velutinus native to western North America, in California and Oregon.
Plant them in spring in well-draining soil, in a sunny location they flower better in full sun. Water them regularly until they are well established. Once established they are drought-resistant. On the other hand, they can be damaged in very wet soil so drainage is critical.
You can deadhead the flower but you don’t have to since that could be a big task given the number of flowers it produces especially a large size bush. For the compact bush, deadheading keeps it going and looks nicer. As to pruning you can prune the evergreen spring-flowering variety after flowers are gone. L ate summer-flowering prune in spring and cut part of the new growth from the previous year.
The deciduous variety probably it is best to prune in early spring as they bear flowers on new growth. If you need to hard prune the deciduous Ceanothus do it in February or March. Propagate Ceanothus from cuttings. semi-ripe cuttings work well for evergreen varieties, especially in summer and autumn. For Deciduous variety, softwood cuttings are better. You may propagate from seeds, you will need to soak them for 24 hours in hot water then they should be exposed to the cold conditions sometimes for a couple of months then planted in a warm environment whereas germination can take several months.