UP THE WALL GARDENS September 02 2015, 1 Comment
When flat space is limited, there’s only one way to go — straight up.
Karen suggests ways and means to create your own vertical garden.
by Karen Sutherland, Pascoe Vale South, Victoria
What’s a wall garden?
Growing produce in cities is always a challenge. Often we only have small spaces with little exposure to sun. We may also move house frequently.
City gardeners need to be inventive, and growing our plants up walls and fences can give us more space to fit in extra herbs and other precious plants.
The use of espaliers, hedges and climbing plants for vertical produce gardening is well known, but wall gardens have recently captured the imagination of city gardeners. striking and practical, they offer maximum impact in minimum space. They also offer good access for gardeners with limited mobility.
Imagine a blank wall in your garden filled with your own fresh pick- ing herbs, full of flavour and at your fingertips. You reach out and pick Vietnamese mint, perilla, Thai basil or coriander straight from your wall garden to wrap around spring rolls or throw into soups.
Or you wander out into your tiny courtyard with a pot of hot water, pluck some leaves from a mix of lemon balm, peppermint, ginger mint and chocolate mint, and have herbal tea ready in minutes to refresh and soothe. all of these thrive in semi-shade, where many produce plants would fail.
In permaculture, herbal wall gardens are a definite zone 1 item, straight out your door, (or window), and easiest to access.
However, with the average price of commercial wall garden systems at around $2000 per square metre (including installation), they are not even remotely in the realm of the backyard gardener.
Don’t despair: with some chicken wire, hessian and potting media, you can make a rustic version of these fancy wall gardens to cover fences or walls with your favourite plants. These wall gardens have the added advantage of being easily moved around a small garden to find sun and shade as needed, or to move with you.
What you will need
The wall gardens shown here were made with a light gauge chicken wire, wrapped around hessian bags filled with a customised media mix. plastic zip ties were used to hold the chicken wire together, but wire could also be used. a bamboo stake threaded through the chicken wire at the top helps to hang the wall garden.
A hessian bag is not essential; hessian can be stitched into a bag with string. This can be done with a bag needle (used for stitching wheat bags together up until the 1960s) or a leather needle. The crucial thing is to have a large eye for the string to fit through. plastic zip ties can also be used to stitch the hessian into a bag.
Remember that in a wall garden, gravity is not helping your plants with regard to moisture retention, so you need to make up a water-retaining media mix.
A great material to use for this is coir, also called coco-peat. This is broken down coconut fibre, which is light (handy when hanging a garden from a wall or fence!), holds moisture well and also ‘wicks’ moisture well, which is to say that moisture is able to rise from the bottom of the media upwards (the same principle used to advantage in wicking beds).
There are various grades of coir available from nurseries and hardware stores, but try to buy a finer structured grade rather than a coarser, free-draining one (more suitable for orchids, for example).
Coir is sold in a compressed brick, which needs to be re-hydrated by soaking in water for 15 minutes or so. It should be mentioned on the packet, but after re-hydrating make a point to wash the coir with fresh water until the water runs clear, to remove any traces of the sometimes brackish water it is processed with. Putting the coir in (clean) plastic plant pots makes it easy to wash and drain.
A good ratio to use for your wall garden media mix is 2 parts coir to 1 part (good quality) potting mix.
You can water your wall garden with diluted seaweed or fish emulsion fertiliser each week, as part of your wa- tering regime, or include some fertiliser in your media mix.
Pelletised slow-release fertiliser is common in most potting mixes, and can be added, or for an organic al- ternative, I have also used well-rotted cow manure (at a rate of 3 parts coir, 2 parts of a rather coarse potting mix and 2 parts well-rotted cow manure) which herbs such as mint, lemon balm and Vietnamese mint enjoy. I wouldn’t suggest using too much manure with plants such as thyme or sage. If using manure, bear in mind that the nutrients will be released more quickly than from a commercial slow-release fertiliser, so at some stage the wall garden will need weekly or fortnightly liquid feeds.
Coir also needs to be balanced with some gypsum (I suggest a cup or two per wheelbarrow load of media mix). Mix all ingredients well.
With the media mix made, and ingredients gathered, you’re ready to assemble your wall gardens and plant!
Wall gardens are similar to any other potted plant, and will need to be watered every day or so, depending upon the weather. use a soft setting on your hose nozzle, or use a watering can. Of course, you could also water them from a watering system from your tank or mains water.
Hessian is a biodegradable fabric, and cannot be expected to last more than a year or so in contact with moisture like this, and a more long-lasting (but not so attractive) wall garden could be made with shade-cloth.
After a year of service, divide your herbs and give half away (which keeps them producing well and shares the plants around) and recycle the media mix into another wall garden for one more year of use. The hessian can be added to your compost bin or worm farm.
Securing the planting pouch with plastic ties.
Securing the back of the planting pouch.
Wall garden ready to plant.
Karen planting seedlings in the wall garden.
A mixed herb and salad wall garden.
Making a wall garden