GREENERY & SHADING

Improving home energy efficiency through outdoor greenery and shading.

The right plants in the right place

Well-selected plants can improve home energy efficiency by providing shade or light in the right place at the right time.

The plants in your garden can have a huge impact on the sunlight or shade your home is exposed to, and the temperature of the microclimate around your home.

Deciduous plants are great for north-facing walls and windows, as they lose their leaves in winter, letting warm sunlight through. Trees, shrubs and vines that shade western walls and windows will protect you from the hottest afternoon summer sun.

For spaces that plant won’t suit, shade cloth, external blinds and awnings offer immediate shade and cooling. Retractable, adjustable or angled options allow you to still access low-slanting winter sun when you want it. Shading is a very cost-effective method for cooling your home and reducing energy bills.

  • Emissions reductions

  • Lower energy bills

  • Better health and wellbeing

  • Biodiversity and nature

Trees do so much more than shade your home. Plants ‘breathe in’ toxic pollutants, cleaning the air, and ‘breathe out’ water from their leaves, creating a cooling effect in their microclimate. Australian natives provide homes for birds and bees, and reduce water use.

Research also shows being surrounded by greenery improves mental health and wellbeing, reducing stress and depression, and improving memory, concentration and creativity.

BENEFITS

PLANNNING AND PRACTICALITIES

Knowing when and where to throw some shade.

Direct sunlight provides much more heat than the surrounding air temperature. Just as you’d want be undercover for the hottest summer days, your home also benefits from being in the shade.

Watch where the sunlight hits your home. What time of day does direct light come through your windows? How does this change throughout the seasons, as the angle of the sun changes? What impact does it have on the rooms inside?

What about outside your house? Are there large trees or buildings next door that provide useful cover? Or are certain windows and walls bearing the full force of hot summer sun?

LET THE LIGHT IN

Deciduous plants lose their leaves in autumn and winter and grow them back in spring, allowing sunlight through when you most want it.

Planting deciduous trees on the northern side of your house will provide shade in summer but let essential sunlight and warmth through in winter, helping to cool and heat your home when appropriate. Direct sun through your windows has a tangible warming effect.

If you have a north-facing patio or pergola, a deciduous vine can achieve a similar effect. Deciduous creepers popular in Perth include:

  • Boston Ivy

  • Chinese Trumpet Vine

  • Chinese Wisteria

  • Ornamental Grape

  • Virginia Creeper

Some deciduous trees that grow well in Perth include:

  • Chinese Tallow

  • Frangipani

  • Jacaranda

  • Golden Rain Tree

  • Golden Shower Tree

  • Leopard Tree

  • Oriental Plane

  • Ornamental Pear

  • Pride of Bolivia

Some plants are deciduous or semi-deciduous depending on growing conditions. Choose plants that you know will drop their leaves in a Perth winter. Most deciduous plants are not native to Australia.

SHADING AND COOLING WITH GREENERY

Shade from trees, shrubs and vines cools your home while providing many other benefits.

Plants offer cooling in two ways:

  1. Shade from direct sunlight

  2. Evapotranspiration (‘breathing out’ water)

This means that more greenery in your garden can cool the surrounding air even if it isn’t shading your house directly. Reducing hard surfaces, such as paving, will cool the outdoor spaces around your home.

To cool your home through shading, plant along western, eastern and north-facing walls. The hottest summer sun is from the west in the afternoon, so this is the most important area to shade.

If trees won’t fit the space, shrubs or vines on a trellis or fence will also work.

If you have, or plan to install, rooftop solar panels, make sure your plants won’t obscure them from the sun.

Aside from deciduous plants outside north-facing windows, drought-tolerant, sun-loving evergreen plants are a good choice. There are native and non-native options that grow well in Perth.

Native plants local to Perth are especially suited to our dry climate and sandy soils. They will be easier to establish and maintain, use less water and fertiliser, and provide better homes for wildlife. Southwest WA is a global biodiversity hotspot, and we have spectacular plants and flowers to show for it.

Native trees and shrubs that grow well in Perth include:

  • Banksia (many varieties) (local native)

  • Bottlebrush (many varieties)

  • Cottonwood Hibiscus

  • Grevillia (many varieties)

  • Lilly Pilly

  • Marri (local native)

  • Red Flowering Gum (local native)

  • Woolly Bush

Native creepers suited to Perth include:

  • Black Coral Pea

  • Guinea Flower

  • Native Wisteria (Hardenbergia)

SHADECLOTHS, AWNINGS AND EXTERNAL BLINDS

For spaces that plants don't suit, shade cloth, external blinds and awnings offer immediate shade and cooling.

Awnings stop direct sunlight coming through windows, without obscuring sight or indirect light. External roller blinds offer much more substantial shading and insulation than indoor fabric blinds.

Angled louvres are slanted just right to let through winter sun (when it’s lower in the sky) but block out summer sun directly overhead.

Trees take time to mature. Shade cloth can be a great interim measure while your plants get established.

Ready-made outdoor blinds are available from hardware stores from $100. Shade cloth starts at $15/m.

Custom-made options can be made to suit your home and style.

External shading is a very cost-effective method for cooling your home and reducing energy bills.

RESOURCES

FINANCIAL SUPPORT

Many local councils in Curtin offer subsidised native plants for your garden through APACE.

Visit APACE nursery in Fremantle.

HELPFUL WEBSITES

SUPPLIERS IN CURTIN

This is not a comprehensive list of suppliers in or around Curtin, but an example of some businesses that our volunteers are familiar with. This is not an endorsement of any of these business by Kate Chaney MP or Electrify Curtin. Please do your own research to decide what’s best for you.