Crop Swap Sydney member Dee has an ambitious vision to turn a challenging plot into a highly productive space. It has been four years in the making and involves copious amounts of clay, sandstone and a large vertical wall, just waiting to be planted out. The problem is how?
When Dee moved into the Berowra property 19 years ago it had been populated by a crazy old man and resembled an urban rainforest. There seemed to be little method to the madness as beautiful orchids sat next to camellias, spiky holly outgrew its position next to the front entrance, and a widowmaker eucalypt towered over the property. Many of these have since gone, but a lovely weeping apple and substantial peach tree both remain.
The original back garden
The site is made up of a sunken area off the house, which will become an outdoor entertaining space. Flanking this is a south-east facing clay and sandstone wall that Dee intends to grow edibles in vertically. This combination of rock, clay, aspect and vertical gardening is definitely an interesting one, but we love a good challenge.
Any gardener knows that the basis of a successful productive garden is in its soil. Traditionally clay soils have a relatively good nutrient composition, have high water holding capacity and a dense makeup. While water is essential in soil, it also needs good drainage so that plants don’t get ‘wet feet.’ Having a dense composition means that roots find it hard to make their way through the medium. Growing vertically is also a challenge as it can be difficult to get water inside the growing cavities and therefore irrigation is normally used.
The back wall
The level above this wall is a flat, sunny space with better soil, and lots of potential. Currently it is an exciting blank canvas. Though the light here is good, we have recommended getting the soil tested by Macquarie University’s VegeSafe as Dee suspects there may be remnants of old chemicals.
Plotting the way forward
We discussed boring holes into the vertical face and creating a type of pocketed, wicking bed system that would promote better drainage and nutrients for perpetual edibles.
This is a layered system that allows plants to draw moisture up through the soil, distributing it more evenly and therefore creating better growing conditions. Traditionally, in a wicking bed, scoria or gravel is used to promote good drainage, with the growing medium on top. Geo textile is then used to separate the water reservoir from the soil so that the plants don’t get wet feet. We would normally always recommend that a vertical garden be irrigated, however depending on the depth of the cavities, direct watering may suffice as wicking beds use very little water.
Image via Image via endlessfoodsystems.com
Throughout this garden plant choice will be very important. Regular replanting in the wall would be difficult so perpetual plants are recommended. With a good water supply, sorrel, sweet violet, mint, short carrots and brahmi could work as well. Native edibles that require less water, such as samphire, would also grow well in unshaded areas of this aspect.
The proposal for the upper level will be dictated by the results of the soil tests. With clear readings, allowing Dee to plant directly into the ground, adding Gypsum and compost would be crucial to break up the clay. Citrus could easily be grown, due to relatively shallow root systems, allowing key nutrients to be added and taken up more easily. A non-grafted Passionfruit (the rootstock of grafted plants tends to take over in sandy soils) could cascade over the wall.
If tests show contaminants in the area, then raised beds would work well and would require much less work to regenerate the soil. In this case Dierdre would also have more plant choice.
With time and planning this space could become a productive system with fruit trees, chickens, bees and a pond (to re-home the tadpoles living on the lower level.)
Amidst this exciting potential, the labour intensive preparation work continues as Dee’s dad excavates the site two full days a week (previously seven days).
The excavator hard at work
Slowly the edibles are creeping in (much to the delight of the resident escapee rabbit from a nearby childcare centre.) A few raised beds on the upper level exist and a holding area has been setup in the front garden where gifts from fellow Crop Swappers are temporarily homed until this grand vision is realized.
After our meeting Dee is hoping to add some citrus. These grow well in pots, can be transplanted, and are an investment, as you shouldn’t harvest within the first growing year. This allows all the plants energy to be directed into building a healthy root system for better health in coming years.
Stay tuned for more updates on this exciting undertaking and if you have any tips or ideas for Dee please let us know.