I enjoyed processing rhododendron cuttings in the greenhouse at the nursery during rain, but only for a limited time. If the rain continued for several days, and I had processed several thousand cuttings, I would prefer any other chore regardless of the saturated and muddy conditions outside. I was consequently amused at how pleased the members of the Monterey Bay Chapter of the American Rhododendron Society were when horticulturist, Peter Moerdyke (my colleague at Bay Laurel Nursery) demonstrated propagation of rhododendrons by cutting at a workshop in Aptos.

There is a prevalent misconception that rhododendrons are difficult to care for and to grow successfully. They however perform well even in the Santa Clara Valley with less attention than more commonly grown roses if their cultural and environmental requirements are fulfilled. The cultural requirements are somewhat specialized and seasonal, but not extensive. Like roses, rhododendrons appreciate seasonal fertilizer and deadheading after bloom.  Pinching promotes structural density among some cultivars, but pruning is very rarely necessary.

Selection of rhododendrons conducive to endemic environmental conditions is simpler than modification of environmental conditions to appease a particular cultivar. Many cultivars have been developed for warmer and arid climates and may perform as well here as the classic cultivars perform in the Northwest.

Rhododendrons that have been grown locally adapt more easily to their new garden environment because the climate is not as unfamiliar as it is to rhododendrons grown in other climates. Rhododendrons from the Northwest may need to adapt to warm and dry air as well as alkaline soil and water. Many of the cultivars that prefer other climates are unable to adapt completely. (Some cultivars that look great at my father’s home in Silverdale are about as suitable to the Santa Clara Valley as locally common Mexican fan palms are to Silverdale.)

Rhododendrons require several years to be marketable. ‘Factory grown’ specimens that have been rushed to grow at the same rate as other crops are of inferior quality with minimal root development. The best specimens are grown by local establishments that specialize in rhododendrons. Wholesale nurseries or growers are not open for retail sales, but their products are available at local retail establishments.

Soil in the Santa Clara Valley and much of the Santa Cruz Mountains is dense and does not drain sufficiently for shallow rhododendron roots. Irrigation should be frequent for rhododendrons as it might be for lawns. However, if irrigation is both frequent and too generous, slowly drained soil remains saturated and established roots rot and new roots are unable to disperse. Drainage should be enhanced with soil amendments such as shredded redwood conditioner. Rhododendrons may otherwise be installed on the surface of dense soil in ‘mounds’ of well drained soil.