NEARLY NATIVE
MAY, 2008

Those evergreen bushes now breaking out in tufts of vivid blue are ceanothus. Californians call them blueblossom, California lilac or wild lilac, although ceanothus is nothing like the familiar, fragrant true lilac. As our climate grows warmer and, intermittently, drier, ceanothuses are valued more and more for their low water requirements. If you can provide space, good drainage and full sun there is probably a ceanothus that’s right for your garden.

Most species of ceanothus occur in Oregon, California and Mexico. Those commonly found growing between the Cascades and the Oregon coast have white flowers, not blue. They are rarely planted except in native gardens and can be difficult to find. (Doak Creek Nursery is one source.) Varnishleaf ceanothus (Ceanothus velutinus var. hookeri) and buckbrush (C. cuneatus) are evergreen. Deciduous red-stemmed ceanothus (C. sanguineus) with purple stems and abundant creamy white flowers in June is recommended as a butterfly host plant.

Some of the most exciting blue-flowered species may not be reliably hardy in Western Oregon. Those that are include a couple of useful evergreen ground covers and some showy garden hybrids. Prostrate ceanothus types vary from extremely flat (and not very weed proof) to spreading mounds 2-5 feet deep and 12 feet wide or more. Among the latter, the widely available ‘Point Reyes’ (Ceanothus gloriosus) is fabulous for covering large banks quickly. The one inch leaves are tough and spiny, the flowers light blue. It needs little or no summer water once established. ‘Heart’s Desire’ is a more compact variety with a 6 foot spread.

Until recently, the most familiar evergreen ceanothus cultivar was ‘Victoria’, a fast-growing plant 6-8 feet tall with glossy one-inch leaves and abundant clear blue flowers. In recent years I’ve been seeing more and more of ‘Julia Phelps’ and ‘Dark Star’. Both have deep blue flowers and leaves smaller than ‘Victoria’. All three have some degree of resistance to browsing by deer. (The resistance of any ceanothus to browsing is highly relative. Let’s just say that those with tiny, tough leaves are most likely to grow fast enough to stay ahead.)

Non-prostrate ceanothus varieties rarely stay below 6 or 7 feet and are often considerably wider. Books says ceanothus resent disturbance, and that can include pruning. Sunset Western Garden Book recommends you avoid cutting off branches more than one inch in diameter, and the authors suggest you control growth by pinching back shoot tips during the growing season. This may keep you busy. Light, regular shearing is definitely an option with easy going varieties such as ‘Victoria’ and ‘Joyce Coulter’ On the whole, though, it’s best to adopt one of two strategies: either expect the plant to take up lots of space and revel in it; or plant one just for the hell of it and replace it when it gets too big.

Ceanothus x delilianus is the moniker for a group of hybrids between a blue-flowered Mexican species and New Jersey tea, a hardy, deciduous plant with low-key white bloom that occurs in parts of east and central North America. The best known offspring of this cross, named ‘Gloire de Versailles’, has long been popular in Europe. In Britain, where heat loving plants need all the help they can get, it is often trained on a warm wall to encourage it. ‘Gloire’ is a taller, more open grower than ‘Victoria’ and kin; the leaves are much larger and the powder blue flowers occur in larger clusters over a longer period. They are fragrant, too.

I’ve been growing a ceanothus of this type in a tub for two years. So far it is only about four feet tall. I know it will get too tall eventually but I’m enjoying it very much in the meantime. A container provides the excellent drainage that ceanothus love, and this one kept most of its leaves through the winter. The only other ceonothus I have at present (also in a pot) is named C. x pallidus ‘Marie Simon’. Hardy and fully deciduous, it has red stems and pleasing light pink flowers.

Ceanothus tends to be fast growing and short-lived. Longevity no doubt relates to soil type, drainage and watering regimes. To keep plants looking their best through the heat of summer they should be watered at least once a month. Many garden hybrids tolerate more regular watering, but most don’t need it.

Three stellar plant sales occur in May, two on the same day. All offer a mix of commercial vendors and donated plants.
17th annual Hardy Plant Sale. Saturday, May 10, 9am-2pm at the Lane County Fairgrounds in the Auditorium Building. More than 25 specialty vendors. All kinds of perennials, trees, shrubs and garden art. Courtesy of The Willamette Valley Hardy Plant Group. A portion of the proceeds helps fund activities of other 501(c)(3) groups.
The Oregon Plant Fair. Saturday, May 10, 9 am-2 pm at Alton Baker Park.
“Fabulous plants, incredible art, music, food, fun” brought to you by Avid Gardeners and the Willamette District Garden Clubs. A portion of the proceeds will benefit GrassRoots Garden, Food for Lane County.
Mt Pisgah Arboretum Wildflower Festival and Plant Sale. Sunday, May 18, 10am-4 pm at Mt Pisgah Arboretum. A large variety of plants, including many native species.

Rachel Foster of Eugene is a garden consultant and author of All About Gardens, a selection of past Eugene Weekly columns. She can be reached at rfoster@efn.org