Basic Outdoor Culture
Here at SBOE, we are partial to orchids that can be grown outdoors. In our subtropical climate, nature provides a very livable range of temperatures, humidity and air-movement; shadecloth or trees filter the sunlight; sprinklers or drip irrigation do the watering, pests are less of a problem, and orchids are enjoyed as part of the whole garden setting. Our nursery is located two blocks from the Pacific Ocean, about two hours north of Los Angeles. In the winter, typical temperatures range 55-70F in the day and 32-50F at night. Light frosts are common; once every five years it may be as low as 27F for a few hours; the most devastating day was in 1990 when temperatures dipped to 24F for 5 hours. Because we are near the coast, many a summer-day is breezy and foggy, never warming above 65F, with the warmest days reaching 80F. Occasionally temperatures rise to 100F, often accompanied by dry winds. Our ‘guestamates’ for temperature tolerance are based on 47 years of growing orchids under such conditions, tales of triumph and failure against temperature extremes by orchid friends around the globe and research on the habitats of orchids in the wild. Each person will need to modify our recommendations to his or her own growing conditions.
Most of our outdoor orchids can endure temperature extremes of 30-90F. We consider all these orchids Temperature Tolerant, although there is some variation between specific groups. All must be able to withstand the winter cool of periods in the 30’s, 40’s and 50’s (F) without deterioration and at least some frost for modest durations. Several types, particularly cymbidiums, require cooling at night and in the winter (the differential between night and day is critical for blooming), and still others require more constant, cooler temperatures. During summer, if it gets too hot for certain genera (masdevallias are stressed above 80F), we run misters under the benches or wet plants down to keep them cool. Mild coastal areas where minimums and maximums are less extreme can grow most suggested varieties, while areas of more extreme heat and cold should select from the hardiest varieties (i.e. 24-100F). There are at least some varieties for even the most extreme locations, provided proper light and moisture. We do not recommend most temperature tolerant varieties for indoor culture; mainly because we find they thrive better outdoors (more robust growth and blooming); however, people living in climates that freeze are able to grow many of these types outdoors most of the year, bringing them indoors at the first frost and for the winter.
These orchids all like bright filtered light. Avoid prolonged periods of direct light or deep shade. Good light is crucial for strong growth and flowering.
Watering, as with all orchids, is done as needed; water thoroughly so that the medium and roots are well soaked (be sure they drain well) and wait until they are almost dry before watering again. Under our conditions, watering once a week with occasional wetting down during warm times is sufficient. Mounted plants are wet down daily on sunny summer days and weekly during the winter, or if they are out in the rain, they need none. In warm, dry areas, water more frequently; about as often as you water your lawn. See our sheets on various genera for more details about potting and growing mediums.
Regular feeding promotes good growth. Use a balanced fertilizer (i.e. 10-10-10) or one a little higher in Nitrogen (10-5-5).