No matter how many years one has
been growing Orchids, each year is a little different and this year
has been no exception. Fall
in the Carolinas has been extremely dry with wonderful bright days and
few clouds. This is similar to the weather in Southern
California where there were once many Orchid nurseries. Typically, short winter days and low light
lead to over watering, but not this year.
Aquifers and rivers are at record
low levels and this can mean a change in the quality of water coming
out of the tap. Hobbyists along
the Coast that obtain water from home wells should be especially wary
of changes in the taste of water, as salt intrusion can occur.
Your Orchids will notice before you do.
Community water systems, even those obtaining water from well
systems, must monitor water quality.
If you have a question about the quality of the water from your
tap the local water system can provide you with the level of dissolved
solids in the water or you can purchase an instrument that will provide
this for around $50. These Conductivity instruments are also handy
when you fertilize because you can measure the quantity of fertilizer
you are adding to your water.
This time of year there is little
need to fertilize Orchids as they are not generally in a high growth
mode. There is always a little
residual fertilizer bound to the bark, pot, and other parts of the media,
which is usually enough for the plant’s needs during winter. Because of the lower light and heat levels, Orchids require less
water. It is a good idea to
wait an extra day after you are sure the plant is ready for water before
watering. The only downside to letting your Orchids get
a little drier than usual is that any fertilizer or salts in the water
bound to the media can be concentrated by extra drying. To counter this phenomenon, water plants very
thoroughly when you do water. This
is best accomplished by wetting the plant and pot thoroughly the first
time around and after you finish all plants, water thoroughly again. This allows salts bound to media to dissolve
and then be flushed from the pot.
It is surprising how much salt
can accumulate each year in a pot and media if proper watering is not
done. Most novice growers ask
how often to water, but do not realize that the nature of Orchid roots
and the media they are grown in makes them different than most house
plants whose roots take up water almost immediately.
Orchid roots must be wet for at least a few minutes before they
shift from a water conservation to water uptake mode.
You can observe the phenomenon in Orchids in baskets as roots
turn green and get thick after watering a few minutes.
This is the point where water is absorbed.
As Cattleyas and Dendrobiums finish
flowering keep them on the dry side.
That means watering less and keeping lots of air moving around
them. It is OK for the bulbs
to shrivel a little over winter, but not to the point where leaves shrivel. Do not apply the same process to miniature
Cattleyas as they do not need a rest period and do not appreciate drying
out.
Some Paphs need attention this
time of year, namely the smallish Brachys and Parvis. Give them a little more light and a little less water to avoid rots.
While they do not have pseudobulbs, they store water in their
thickened leaves, so watch for leaf shriveling as an indication that
they have dried more than need be. If you do this, plants will have good root
systems and can quickly soak up water when you next water them.
Phalaenopsis spikes should be staked
if that has not been done yet. If
spikes tend to go in another direction besides up, it will be necessary
to straighten them so that the spike is vertical. It may be impossible to straighten the base
of the spike, but a longer piece of tie wire attached to the base of
the stake will secure the lower part of the spike as the upper portion
is pulled closer to the stake. Do
not tie spikes tightly against the stake until the spike is mature and
the first bud has opened. At this time the spike will not lengthen and
the spike can be firmly secured to the stake.
For standard Phals, the last tie should be just above either
the last node before the first flower or just above the second node
before the first flower depending on your preference.
There are also those that prefer to tie the entire spike upright,
although this is not looked upon favorably by AOS judges. Once
Phals have set spikes they need a minimum of 65 ºF at night to avoid
rots. Keep lots of air moving around both leaves
and flowers to avoid those tiny spots from Botrytis that destroy flowers. Flowers should be clearly moving to avoid this
problem. Remove dead flowers
and other decaying materials from benches to limit the number of Botrytis
spores.