The
American Orchid Society (AOS) has developed culture sheets for many
different types of orchids. These sheets are available on their website
and can be downloaded and
printed free of charge.
A beginning grower can usually achieve
reasonable results by following the general culture guidelines provided
by the AOS and others. However, in order to be a good or excellent grower,
you need to watch and listen to your plants and adapt your own particular
cultural practices to their individual needs.
There is no single "right"
answer to orchid culture. What works well for one person does not necessarily
work for another. Why? There are just too many variables for a hobbyist
grower (or even most commercial ones) to precisely control. For example,
differences in available light, temperature and potting media will all
affect watering frequency requirements.
The orchid plants offered on this website
were grown in a greenhouse under the following general conditions:
Temperature: Summer
- 50-55° nights and 80-85° days. Winter: 55-60° nights and
65-70° days.
Humidity: 50-65% during the day,
higher at night.
Light: 1500 - 2500 footcandles.
Our plants get more light (particularly in the summer) than that provided
by some growers. Under higher light conditions, air movement is more
important to prevent leaf burning and discourage pests.
Water: We use well water with
about 280 ppm in dissolved solids. Generally, a relatively low ppm (<
100) is desirable. However, depending on the particular mineral content,
a natural water source may actually provide valuable trace elements
that are necessary for proper plant metabolism. Most orchids in nature
are accustomed to relatively pure water sources. If your water supply
has more than 500 ppm in dissolved solids, you may want to consider
an alternative source, such as rain water or Reverse Osmosis (RO) filtered
water. In the summer, we water about once every 1 to 7 days, depending
on the type of plant and pot size. In the winter, we typically water
once every 7-10 days and only on sunny days (when possible).
Fertilizer: We fertilize "weekly,
weakly" using a balanced fertilizer (e.g. 10-10-10) containing
additional trace elements. (The purer your water source, the more important
supplemental trace elements become because waer source is less likely
to contain all of the micronutrients that are required for good plant
metabolism.) During warm temperatures and active growth, we use a fertilizer
mixture with a total dissolved solids of around 500 ppm, including the
280 ppm dissolved solids from our water source. (Depending on the starting
ppm of your particular water source, this concentration can typically
be achieved by using 1/2 to 1/4 the strength recommended on the fertilizer
label.) We continue to fertilize in the winter, but at a reduced concentration.
Prior to fertilization, the plants are watered generously with regular
water to flush accumulated salts from the potting media and to pre-wet
the plant roots. The fertilizer mixture is then applied a few minutes
later.
Air movement: Several over bench
fans provide air circulation 24 hours per day, 365 days per year.
Potting Media: For most plants offered, we use
a mix consisting of 4 parts fir bark, 1 part perlite and 1 part charcoal.
The particle sizes used in the mix are varied according to the type
and size of plant. For example, we use a mix with medium bark chips
and large (#3 or #4) perlite for most blooming size Cattleya plants,
whereas we use a fine bark mix for most Oncidium. We use a fine bark
mix for seedlings of most genera.
Since orchids have varying cultural
preferences, we try to take advantage of certain microclimates within
the greenhouse. For example, sun loving Vandas are grown in baskets
hung near the greenhouse roof. Cooler growing pleurothallids are grown
near the evaporative cooler pads so that they will receive plenty of
cool, moist air in the warmer months.