University of Vermont Extension
Department of Plant and Soil Science
Dr. Leonard Perry, Extension Professor
University of Vermont
can give your home "curb appeal," but did you also know that it may
keep your home cooler and reduce both summer and winter energy bills? Proper
landscape design, along with associated plant choices, can reduce energy
consumption and cool your home.
Just as you can benefit from
the shade of a tree on a hot summer day, so can your home. Planting deciduous (those shedding leaves in
fall) trees on the south and west sides of buildings provide shade in summer,
and allow the winter sun to reach the building through the then bare
branches. Depending on location, shading
the roof of a house can lower inside temperatures 8 to 10 degrees (F). Some
good choices for northern New England are maples, oaks, and the less commonly
used beeches and ash.
the summer, beat the heat by planting trees to shade the roof, walls, and
windows of your home. Shading even 20 percent of the roof for an entire
day significantly will reduce your energy costs. The type of tree you
plant will determine the amount of shade provided. Be careful not to plant too
close to the house to avoid damage to the foundation or siding. Keep
mature height and spread in mind when planting near homes. A common
mistake is to plant too big a tree too close, only to have it cover the house
in a few years.
city of Akron (Ohio), using software and formulas developed for the tree
calculated the energy-saving value of two dozen trees in
2012. Most cost effective, with average
dollar benefit per tree, were pin oak ($60), silver maple ($61, not a good
choice for many
landscapes as it can be short-lived and drop many
branches), Norway maple ($49, not
recommended now as it is invasive in many areas), basswood
or linden ($49), red maple ($39), honeylocust ($32), and red oak ($28).
Plant trees along the western and southern
sides of your house, taking care to keep them away from power lines and other
obstructions that may get in the way as they grow. If you are just starting out, or just can
plant one tree, choose the west side. In
the morning, the summer sun beats on the east side of buildings, but these
aren’t heated significantly being cool from the night. During midday, although the sun is from the
south, it is high in the summer sky, so has less impact on south-facing
walls. In afternoon, especially between
3pm and 5pm or so, the sun is lower in the west, and the air is warmer, so
there is a much greater need to shade the west side of a building.
use an air conditioner, planting a flowering tree or shrub near the unit not
only improves aesthetics but can increase the life of the compressor. The shade
reduces the strain on the unit caused by operating it for long periods of
time. Just make sure you don't block the air intakes. Instead of a
tree or shrub, you could erect a trellis two to three feet away from the unit,
which allows access, as well as good air circulation. Train deciduous
vines to grow up the trellis. Some possibilities are clematis, akebia,
also can be trained to grow up an arbor or porch to cool your home. Vines
grow quickly and are a good choice if you have limited ground space or want to
start saving on your energy bills immediately. In winter, trim back the vines to let in more
sunlight. Plant perennial vines like
hops if you have a big trellis, or string coarse twine (like baling twine) up
to the eaves. Hops, once established after the first year, will provide lots of
cover quickly. Other good vines are Dutchman's
pipe or trumpetcreeper, both of which can grow large enough to shade most of
your home in as little as five years.
Ask the experts at your full-service garden
center what they recommend for vines best for your area and situation.
Not all vines are a good choice for landscaping as some such as Boston ivy may
damage paint, shingles, brick, or wood by retaining moisture, especially if
they are growing right on a wall or side of building. One way to avoid
this is to attach a trellis to the side of the house and train the vines to
climb that, and not the house.
can be planted to form a living fence between your house and the
sun. Shrubs also
can be planted near sliding glass patio doors and
windows to shade architectural features such as these, which transfer heat
during the summer months. Choose varieties that grow about six to eight
feet tall, high enough to block the late afternoon sun. Some examples are
serviceberry, several dogwoods (shrubs not the small trees), forsythia (quick,
vigorous), mockorange, and lilacs. For all of these, check to make sure
the cultivar you have chosen will have the height you need, and not be a dwarf
variety, and allow them the room they need for spread.
more information about these and other woody plant choices, order a copy of
book Landscape Plants for Vermont
from the Vermont Master Gardener program (www.uvm.edu/mastergardener). Your local nursery or garden center also
should have a large selection of trees, vines, and shrubs for your
energy-saving landscape. Or work with a landscape professional, and start
saving energy dollars today!