Environmental and
Mechanical Pollination
Setting a conducive environment for
pollination is critical, especially if there
are no natural pollinators. This does not
necessarily involve mood music and dim
lighting, although attention to the right
temperature and humidity levels, and
even the time of day, is highly suggested
if pollinating by hand.
If the temperatures are not correct,
the plants cannot properly form their
blossoms and release or be receptive
to pollen. Temperatures for optimum
pollination vary between plant species,
but generally, night time temperatures
should not fall below 55˚F and daytime
temperatures should not exceed 85-90˚F.
Humidity levels need to be controlled,
or at least monitored, to know when
to pollinate. If the humidity levels are
too high, the pollen will likely stick too
much to the flower and be too difficult
to disperse. Humidity levels should be
between 50-80 per cent, with most growers
attempting to seek a humidity
level of about 70 per cent.
Once the temperature and
humidity levels are within
optimum range, pollination
will be most successful
between mid-late morning and
early to mid-afternoon. This is
when most blossoms are fully
open and most accessible for pollination.
Aiding in Mother Nature’s processes is nothing new and
neither is manipulation of pollination. Some techniques used
today have been done for hundreds of years or more. In some
cases, only the tools have changed, but the method hasn’t.
Pollination of flowers can be achieved by various hand tools.
Some of these are common household items and others are
more specialized. An artist’s paint brush has been used for
hand-pollination for a very long time. The grower essentially
swabs the pollen from the male flower and then swabs the
same brush across the female flower. This is repeated across
each flower that’s desired to be pollinated. Once is not often
enough with this method. Some flowers require pollination
dozens of times to bear fruit. Many growers will perform this
process for the entire duration of a plant’s flowering cycle.
Toothbrushes are also used. Recently, electric or battery-pow-
ered vibrating toothbrushes have been used. While this
method may mimic the vibration of a pollinator’s wings, it
should be done with the utmost care as the vibrating brushes
can also damage the flower’s reproductive capability if done
too vigorously. Cotton ear swabs can also be used.
There are many devices on the market for the professional
and hobbyist alike to perform hand pollination. They
range in complexity and cost from modest and simple to
expensive and elaborate.
“ A i d i n g i n M o t h e r N a t u r e ’s
p r o c e s s e s i s n o t h i n g n e w. ”
40
Maximum Yield
Most greenhouses have some sort of air movement system
in place even if it is nothing more than a few fans. Fans help
excess water to evaporate quicker and lower the incidence
of diseases, but those same fans can help with pollen
dispersal. While it is more of a saturation bombing than a
strategic one, fans will help released pollen find some of its
target. Strategically placing fans at flower level during times
of pollination helps increase that ratio of off- to on-target
hits. An occasional or even steady breeze will not just aid
in plant pollination, studies have shown that greenhouse-
reared plants are often stronger when they are exposed to
some amount of swaying or exposure to moving air. Some
high-tech greenhouses have vibrating tables or mechanical
brushes that gently and occasionally pass over or by each
plant. While systems such as these are generally cost-
effective for the average to even larger grower, when there
are millions of plants to be pollinated, there are only so many
viable days to get the job done and mechanization can help.
Whether pollinating by hand, using bees, or releasing
beneficial insects to do the job, many growers have many
methods to help them achieve maximum yields on their
greenhouse crops.