What can you do with an empty concrete space that doesn't look anything like a garden?
At Birdies Garden Products, we're finding out.
At our Gold Coast headquarters, an area that was once part of the car park is being transformed into a productive edible garden using Birdies raised garden beds.
Rather than simply showing you the finished result, we're documenting the entire transformation from the beginning.
In Episode 1 of Carpark to Edible Garden, we start with the blank space, improve the surrounds, prepare the first garden areas and transplant a 2-year-old lime tree into its new raised bed.
If you're looking for raised bed garden ideas for beginners, this series shows how a garden can evolve one practical step at a time.
Follow the full Carpark to Edible Garden series as the space takes shape.
Starting With an Empty Space
Every garden starts somewhere.
In our case, we're starting with a large concrete area at Birdies headquarters.
There is no lawn to remove and no existing garden soil underneath most of the area. That means the garden has to be designed around the surface we already have.
Raised garden beds make this possible because they allow us to create dedicated growing areas above the existing ground.
Over the course of the series, we'll show how the beds are positioned, filled, planted and connected into one complete edible garden.
We'll also cover some of the practical considerations involved when putting raised garden beds on concrete.
Can You Put a Raised Garden Bed on Concrete? – Episode 2
Make the Space Feel Like a Garden First
One of the first lessons from this project is that you don't have to start with plants.
Improving the surroundings can immediately change how a space feels.
Behind the new garden area was a fence overlooking parked cars, so we installed inexpensive bamboo screening to create a more attractive backdrop.
It was a simple change, but it immediately made the area feel more like a garden rather than part of a commercial car park.
When planning your own garden, look beyond just the beds.
Consider:
- What will you see behind the garden?
- Are there fences or walls you can soften?
- Where will the garden boundaries be?
- How will paths and surfaces look?
- How can you make the area feel inviting before anything is planted?
Small visual improvements can make a big difference.
Using Garden Edging to Define the Space
We're also using Birdies steel garden edging around the perimeter of the new garden.
Normally, the stakes used with this edging are driven into the soil.
Because much of our garden is being installed on concrete, we modified the stakes by creating a 90-degree angle and securing them to the concrete instead.
The edging has two jobs.
It gives the garden a finished border and helps contain the bark mulch that will eventually cover much of the visible concrete.
For gardeners working with patios, paved areas or other unusual spaces, this is a good example of adapting a product to suit the site rather than assuming every garden has to be built in exactly the same way.
Covering Concrete With Bark Mulch
One of the easiest ways to change the appearance of the space is to cover much of the visible concrete.
We're using a thick, bark-style mulch between the raised beds.
Besides being great to walk on, it helps visually transform the area and creates the appearance of a more traditional garden surface without having to remove the concrete underneath, and it also helps reduce radiant heat in our subtropical climate.
Combined with the steel edging, it helps define the garden and gives us clear pathways around the raised beds.
The important point is that a productive garden does not necessarily need to start with a perfect patch of soil.
You can design around the space you already have.
Choosing Raised Beds for Different Jobs
One of the benefits of a raised bed garden is that every bed does not have to serve the same purpose.
In this episode, we introduce one of our tall round Birdies beds.
It measures approximately one metre in diameter and we're using it to create a new home for a young lime tree.
The additional depth provides a substantial volume of growing medium, which makes the bed well suited to support a lime tree.
Other beds throughout the project will eventually be used for vegetables and other edible plants.
This is worth considering when developing your own raised bed garden.
Rather than choosing the same bed for everything, think about what you want each area of the garden to do.
Explore Birdies Raised Garden Beds
Moving an Established Lime Tree Into a Raised Garden Bed
The lime tree used in the project was already growing successfully in one of our shorter round beds.
Rather than starting again with a new tree, we decided to move it into a taller round bed in the new garden.
Before moving the tree, we removed the existing fruit to reduce some of the stress on the plant during transplanting.
The old raised bed was then lifted away from the root ball.
One useful feature of our modular raised beds is that, depending on the bed and installation, they can often be moved when the garden changes. This is particularly useful for fruit trees in our round beds, as every few years you can lift the short round bed, trim the roots back by a few inches and add a fresh soil-and-compost mix. This helps prevent the tree from becoming root-bound, particularly if the bed is sitting on a hard surface such as concrete.
Before we moved this tree, we trimmed around the edge of the root ball with a sharpened spade so the tree could be lifted more easily.
With the new bed already positioned, the lime tree was ready for its new home.
Preparing a Fresh Soil Mix
We didn't simply throw away all the existing growing medium.
Some of the original soil was still in reasonable condition, so we reused it and improved the mix.
For this particular project, we added fresh soil and compost along with coarse river sand to improve the long-term structure of the mix and help prevent excess settling over time.
We also incorporated rock minerals into the mix before planting the tree.
The aim was to provide the transplanted lime tree with a refreshed growing environment while making use of some of the material we already had.
When refreshing soil in an existing raised bed, the exact amendments you need will depend on the condition and composition of the soil you already have.
For new beds, use the Birdies Soil Calculator to estimate how much growing medium your chosen configuration requires.
Use the Raised Bed Soil Calculator
For more guidance, see How to Fill a Raised Garden Bed.
Keep a Transplanted Tree at the Same Planting Depth
When the lime tree went into its new bed, we positioned it at the same soil level it had been growing at previously.
Once positioned, the fresh soil mix was added around the roots and the tree was watered thoroughly.
We watered it in with liquid seaweed and a fish-based amino liquid fertiliser, which is essential for helping to prevent transplant shock.
Finish With Mulch
The last step was adding mulch over the soil surface.
Because we're in Queensland, sugarcane mulch is readily available and works well for this application.
Other organic mulches such as pea straw or lucerne can provide similar benefits.
Mulching can improve moisture retention by up to 70% and help prevent weed growth.
It also gives the raised bed a clean, finished appearance.
What We Learned From Episode 1
The first stage of the Carpark to Edible Garden transformation provides a few useful ideas for anyone starting a raised bed garden.
- You don't need perfect ground. Raised beds allow productive growing areas to be created in spaces that might otherwise be difficult to garden in.
- Start with the whole space, not just the beds. Screening, edging and pathways can completely change how a garden looks and feels.
- Different beds can have different purposes. Some can grow vegetables, while others can support fruit trees, herbs, flowers or other garden features.
- Reuse what makes sense. Existing plants, beds and growing media may be incorporated into a new garden rather than starting entirely from scratch.
- Build the garden gradually. You don't need to complete an entire edible garden in one day. This project will develop in stages, and we'll show each one.
Starting Your Own Raised Bed Garden
If you're planning your first raised bed garden, start with the space you have rather than the garden you think you're supposed to have.
Look at:
- available sunlight
- the surface underneath the garden
- access around the beds
- bed heights and configurations
- drainage
- pathways
- what you want to grow
- how the garden might expand later
You can also use the Birdies Garden Planner to map your area and experiment with different bed layouts before you start building.
New to planting? Read our beginner's raised bed planting guide.
What's Next? Installing Raised Beds on Concrete
With the first stage complete, the next challenge is one that many gardeners ask about:
Can you put a raised garden bed directly on concrete?
In Episode 2, we'll look at preparing raised beds for a concrete surface, including what to consider underneath the bed, drainage and how to stop soil washing out from the bottom.
Episode 1 FAQs
Can you start a raised bed garden on concrete?
Yes. Raised garden beds can be used on suitable hard surfaces, but drainage and the bottom of the bed need to be considered carefully. We cover this in detail in Episode 2.
Can you grow a fruit tree in a raised garden bed?
Yes, fruit trees can be grown successfully in raised beds. The container needs enough growing volume for the tree and its root system, and the tree still needs suitable soil, drainage, water, sunlight and nutrition.
Do I need to remove concrete to create a raised bed garden?
Not necessarily. The Birdies Carpark garden demonstrates how raised beds can create growing areas above an existing concrete surface.
What can I put between raised garden beds?
The choice depends on your site and preferences. In this project, we're covering the concrete with bark mulch and using steel edging to keep the material contained.
Can I move a Birdies raised garden bed?
Many Birdies beds can be moved once empty, although size, configuration and installation will affect how practical this is. In Episode 1, the existing round bed was lifted away so the established lime tree could be transplanted into another bed.
Explore every stage of the project on the Carpark to Edible Garden series page.
