The only real rule of orchid growing is that the rules are just
guidelines. Winter was brief and many different orchids are both
blooming earlier and initiating growth early relative to most years.
Orchids that rely on day length instead of temperature for blooming are
following their normal blooming and growth pattern. Readers of this
column know my normal advice is to limit fertilizer applications to
warmer months, but this year is different because the environment where
my orchids are growing has been different. My orchids that rely on
temperature to start are in a different growth stage than those that
rely on day length. How do I know that some have started their growth
cycle and others not? Should fertilizing applications begin if some
orchids are growing and others are not?
There are many hanging orchids in my greenhouse, not just because of
space, but because they are some of the “canaries” that tell me how my
orchids are interpreting light levels and temperatures. Especially
important in my greenhouse are bifoliate cattleyas, such as C leopoldii
and C guttata. When these species initiate their new growth, spring is
officially here no matter what the calendar says and they are getting
close to initiating new growths.
Many of my spring blooming cattleyas and paphs are orchids that use
temperature to tell them when to grow and flower. Unfortunately, this
year these will be finished flowering when the spring orchid shows need
exhibition plants. Many of these have almost always bloomed within a
week or so of the same time each year, but this year will be an
exception based on buds I see swelling in the sheaths.
When orchids initiate new growths, it is time to begin using fertilizer
regularly and at higher doses. After several months of flushing during
the fall and winter, nutrients adhering to media have largely been lost
or used up. During the last several years, I have limited fertilizers in
an attempt to avoid producing lush foliage that can be attacked by
bacteria and fungi.
There are some orchids that do receive regular fertilizer, albeit at
lower levels in winter. Those include orchids that are growing and
blooming such as phals and paphs, which I keep in different places. Many
cymbidium growers follow a similar fertilizer regimen, but use
fertilizer higher in phosphorus, the middle number, starting in fall.
Hobbyists with just a few plants have an easier time making the decision
because they can look at each plant and decide to fertilize or not. This
is really easy if Nutricote, which lasts six months, is your fertilizer
of choice. The balanced formulation is an excellent one for all orchids
and safe to use. I usually add it to the surface of the medium in early
March, but recommend adding it now if your orchids are starting to grow
new leaves or breaking eyes for new pseudobulbs. If you cannot find
Nutricote in your local store, check with Carter & Holmes Orchids. They
sell small quantities. If your temperatures have not been as warm as
here in north Florida, you might need to wait a little longer. Let your
orchids tell you when you need to begin adding fertilizer.
It will be interesting to see if there will be extra bulbs or leaves
this year with a longer growing season.