When dialing in the climate in your
greenhouse, think about Goldilocks.
The temperature shouldn’t be too hot
or too cold, the air shouldn’t be too
moist or too dry, and the air shouldn’t
be too stagnant or too breezy. Here’s
how to get everything just right.
G
reenhouses are an excellent way to extend your
growing season. They allow you to enjoy a warm
oasis and eat fresh vegetables throughout the winter.
However, if your greenhouse’s climate is not dialed in,
you’ll have nothing more than a hot house full of shriveled
plants with moisture dripping from the walls. When
growing in a greenhouse, you take on Mother Nature’s job
of creating the correct temperature, humidity, and air flow.
Optimizing the climate in your greenhouse is essential,
and there are many options and techniques to help you
create this ideal environment.
Temperature
Greenhouses capture heat efficiently, even in the cold
winter months. Your goal is to keep the temperature in the
proper range for growing. In the summer, you’ll want to
maintain your daytime temperature at about 75-85˚F and
nighttime temperature at about 60-75˚F. In the winter, keep
temperatures between 60-70˚F during the day and as low
as 45-50˚F at night. The exact temperatures you maintain
depend on the crops you grow and their preferences.
Many factors influence the temperature in your green-
house, including light, outside temperatures, and air flow.
Four methods commonly used for cooling your green-
house are shading, evaporative cooling, fogging systems,
and thermal mass reservoirs.
While shading is effective at reducing temperature, it
also reduces the amount of light reaching your plants by
50-60 per cent, which can inhibit growth rates. Sometimes,
however, this trade-off is necessary to ensure your plants’
survival. To create shading, you can purchase shade
cloth, paint-on materials, or adhesive compounds that
can be applied directly to the glass for a more permanent
solution. There are also roll-up screens made of wood,
aluminum, vinyl, or plastic that come with pulley and
rope systems to allow for adjustment based on light and
outside temperature. You can grow trees and plants next
to the greenhouse as a source of shade too. You can even
grow trees or trellis grapes inside your greenhouse to
supply shade to other plants. The large size of the grape
leaves have the additional benefit of acting as a natural
evaporative cooling system.
Maximum Yield
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