What’s So Important About Microclimates?
Ecosystems are made up of many niche environments. This
wonderful diversity results when organisms are drawn to
or adapt to small but always significant changes in their
surroundings. Microclimates, or unique climatic profiles
within a small area, play a role in this. It may look as though
the conventional suburban backyard is pretty lacking in
exploitable changes in climate and other growing conditions,
but that’s not true. Your summer landscape is rich with
microclimates. Even better, when you understand them and
stop being such a stickler for geometric precision in some of
your planting strategies, microclimates can help you become
a better gardener. Let’s look at how it works.
Create the Climate You Need
The term “microclimate” may sound like a newfangled market-
ing ploy, but this approach to cultivation has been around
for centuries. One elegant example of creative microclimate
modification is the classic three sisters planting model used by
the Iroquois Indians as early as the 1300s, according to the Old
Farmer’s Almanac. You’ve probably heard of it. On the surface,
it’s a companion planting strategy for corn, beans, and squash:
the corn provides a support for the beans; the beans contribute
nitrogen; and the squash leaves offer cooling and moisture
protection to the roots of all three plants during the summer heat.
In the cold, damp northeastern climate, the Iroquois
planted the three sisters together on small hills, which warmed
the early-season soil and kept it from becoming too wet.
“
This wonderful
diversity results
when organisms
are drawn to or
Adapt to small
but always significant
changes in their
surroundings.”
50
Maximum Yield
This plan fostered plants earlier and encouraged good
drainage. The height differences and close proximity among
the trio were useful, too. They produced a layering effect
that improved light management and created an organic
fortification against wind and heavy rain. The three sisters
story shows us how small, focused plant and environmental
choices, when combined, can produce impressive results.
While you’re in the thick of performing gardening chores
this season, start noting how microclimates work in your
landscape. Here are some basic factors to keep in mind.
DIRECTION OR EXPOSURE — You’ve probably already
observed a southern exposure has a long growing season
and tends to be warmer and sunnier, while a western
exposure is typically hot and dry. It’s also obvious to even
a casual gardener that northern exposures receive the
least amount of sun overall, and eastern exposures usually
receive gentle morning light and present fewer problems
with afternoon heat. Understanding the benefits and
drawbacks of different directional orientations is a key
component of good microclimate management.
LIGHT, DAPPLED LIGHT, OR SHADE — Directional light
exposure is a mainstay of light planning in the garden, but
factors like the shade and shadows cast by structures, or the
dappled light under a tree canopy, play a role, too. Even the
stippling created by tall plants on their smaller neighbors
has the potential to be useful, or detrimental, depending on
the plants and planting strategies involved.