How I created a mini food forest in my small urban backyard

In the small backyard of my urban Adelaide home, I'm creating a mini forest. An edible one, at that.

This is permaculture food forest-style gardening, in which layers of perennials (plants that live for more than two years) are grown together to create a low-maintenance edible ecosystem.

And already, just a few months after planting, my mini food forest is looking beautiful and providing for my dinner table daily – while requiring surprisingly little work.

Food forests are also water-hardy, heat-resilient and can be grown in even the smallest of gardens. Here's how to create your own.

Adapting food forest theory to small urban gardens

The food forest idea was developed by English horticulturist Robert Hart to mimic a forest edge and stack plants vertically, allowing you to grow a heap more food even in small spaces.

Often, food forests are associated with larger gardens, such as Gardening Australia presenter Hannah Moloney's 3,000-square-metre block in Hobart, where she's planted a beautiful sprawling food forest.

By contrast, my Adelaide block is just a sixth of that size, at 478 square metres.

On bigger blocks, you might incorporate the full seven layers into your food forest:

1. 1.A canopy layer of large fruit trees.
2. 2.A mid-storey layer of smaller fruit and nut trees, or those on dwarf rootstock.
3. 3.A vertical layer of vines and climbers, such as peas and beans.
4. 4.An understorey layer of shrubs such as currants and berries.
5. 5.A herbaceous layer of perennial veggies and herbs.
6. 6.A ground cover layer of living mulch, such as warrigal greens.
7. 7.A rhizosphere or underground layer of root crops such as carrots.

On a smaller scale, you simply wind back the number of layers you choose to plant. In my small urban garden, I've opted for four food forest layers.

How I stacked my food forest layers vertically

Firstly, in preparation for food forest gardening, I grew a green manure across the entire bed to fertilise and enrich my soil cheaply and organically.

Then, I created a mid-storey canopy by planting four fruit trees relatively closely together: a pomegranate, a self-pollinating dwarf Stella cherry, a mulberry and an orange tree grafted with two varieties (Valencia and Washington Naval).

But I don't want these fruit trees to get too big, as they'll block crucial sunlight into my small garden.

So, I'll keep each tree pruned to about head height, which will also make fruit picking so much easier. (The book Grow a Little Fruit Tree by Ann Ralph is an excellent resource for maintaining compact yet abundant fruit trees in city areas.)

Here, I've deliberately prioritised perennial plants – those that live for more than two years – including asparagus, strawberries, yam daisies and comfrey. This is another permaculture style of gardening, which gradually creates less work over time as you reduce the need to replant annuals each year.

But for this first year, while my fruit trees are small and the garden bed has ample sunlight access, I've also thrown in a heap of edible annuals, including lettuce, rocket, spinach, mizuna, chicory, coriander and dill.

I'll let these annual plants flower and set seed, in hopes they'll naturally pop up again next year.

Climate-resilient benefits of food forest gardening

Food forests are an excellent climate-resilient gardening model, with trees helping to sequester carbon.

Edible forests tend to require less water and be more heat-resilient because the layers provide cooling shade for soil and plants beneath — a crucial consideration for me here in Adelaide, where temperatures regularly soar above 40 degrees during summer.

To help further save water, I've added drip irrigation beneath my food forest, which delivers water directly to the plants' root zones so I can water less frequently and more deeply.

Food forests can also be less susceptible to pest predation, as the abundant biodiversity of plants helps bring in beneficial predator insects while slowing down pest insect movement.

And in my patch, I've stacked another function into my food forest by planting it up against my chicken pen, so my hens can peck through the fence and help themselves to fresh leafy greens.

As our cities become increasingly urbanised, creating vast concrete food deserts, planting a mini food forest is a simple way to grow low-maintenance healthy local food, while cooling and beautifying your own patch.

Koren Helbig practices permaculture and grows organic food in the backyard of her small urban Tarntanya/Adelaide home.