How to Overcome the Challenges of Balcony Gardening in Canberra’s Climate
Balcony gardening in Canberra can be extremely rewarding, but its harsh climate—ranging from freezing frosts to blistering summer heat—presents serious challenges. Without the right preparation, these extremes will lead to a failed project.
In this post, we’ll explore the specific climate challenges Canberra’s balconies face and provide strategies to help you create a garden that thrives despite these obstacles.
Architect Philippe Baumann's Brooklyn Home.
Beautifully blending wild elements with the structure of a deck for human habitation.
The taller plants here would be creating a microclimate for the plants below. Added to by the living ground cover and mulch.
In Canberra, all of these plants would need to be frost hardy to -7°C
The substrate here would have been installed at a minimum depth of 300mm.
Challenges and Solutions
Extreme Temperature Fluctuations
The Challenge: Many Canberra balconies experience intense heat in summer and freezing cold in winter, often more extreme than ground-level gardens due to exposure. The severity of these conditions varies based on the balcony’s aspect. (You can read more about balcony aspect here.
The Solution: Plant strategically to create a microclimate. Use larger pots for trees and shrubs that provide shade in summer and protect smaller plants from temperature extremes. Choose resilient plants that can handle both ends of the spectrum.
Harsh Weather Conditions
The Challenge: Wind, frost, and harsh sunlight create difficult growing conditions. Pots may dry out, roots may overheat, and plants can struggle to survive.
The Solution: The goal is to create a microclimate, but additional measures such as windbreaks (trellises or screens), pot insulation, and shade for pots are helpful. Mulching with gravel reduces evaporation and prevents mulch from blowing away, while deciduous trees and vines can act as seasonal shields.
Limited Root Space
The Challenge: Small containers limit root growth, making it hard for plants to establish themselves.
The Solution: Opt for deep containers and use a layered planting approach, mixing trees, shrubs, and groundcovers to maximize root space. Ensure the substrate is nutrient-rich, has both organic and non-organic components and is lightweight. I’ll show you my substrate mix in post 10.
Interestingly, limited root space can work to your advantage. Large trees that wouldn’t normally be suitable for a home garden can grow on a balcony in a pots without getting huge, in a similar way to how bonsai works, allowing you to play with species to otherwise may not have the opportunity to.
Weight Restrictions
The Challenge: Balconies have weight limits, restricting how much soil and water plants can hold.
The Solution: In-depth planning is required here. My personal growing substrate recipe balances weight and nutrients by using a mixture of recycled crushed brick, premium potting mix, biochar, and vermiculite. This combination keeps the pots lighter while still providing a strong nutrient base. If your calculations indicate that weight is a problem, reduce the amount of substrate by creating voids in pots using drainage cells, lined with geotextile to prevent the growing medium from seeping in.
Drainage Issues
The Challenge: Without proper drainage, containers can become waterlogged, leading to root rot. Additionally, poor balcony drainage can cause water to accumulate and leak into apartments below.
The Solution: Ensure pots have sufficient drainage holes and are slightly elevated to allow water to escape. If your balcony has floating tile applications, remove a tile and install your planter in its place to allow better drainage and slightly reduce the overall weight of the space.
Water Management
The Challenge: Canberra’s hot summers cause pots to dry out quickly, requiring frequent watering.
The Solution: Large pots reduce water evaporation, but installing wicking pots, a dedicated irrigation system & ensuring you have quick and easy access to water from a balcony tap can make keeping your garden watered easier.
Maintaining Nutrient Levels
The Challenge: Containers don’t retain nutrients as well as in-ground gardens, making it difficult for plants to get what they need.
The Solution: Use of slow-release organic fertilizers or alternate between applications of liquid fertilizer and Seasol every few weeks. For busy individuals, consider connecting these to an automatic watering system for convenience.
New York Highline in Summer, designed by Piet Oudolf.
One option while planning a balcony garden is to plan a deciduous perennial garden which will change dramatically with the seasons. Gardens like this will need plenty of water in summer but are well adapted to surviving both hot and cold temperature extremes.
New York Highline in Winter, designed by Piet Oudolf.
Overcoming Canberra’s climate challenges requires thoughtful planning and plant selection, as well as solutions for managing temperature fluctuations, drainage, and space. I’ll expand on many of the solutions listed above in the next posts.
Want to keep reading?
Check out the next post in this series The Benefits of Using Native Plants for Balcony Gardens in Canberra.
Want expert help?
Check out my Balcony Design and Construction Services page.
