Vertical gardens can get a bad name when they do not work for the plants. I have seen DIY vertical garden products being sold in local garden centres where the soil depth is 100- 150mm. It is not surprising that these fail rapidly.
Research around the world has shown that in shallow soils, the plants that are most likely to succeed are succulents. To grow a wider variety of plants you need a soil depth of 200 mm.
Many of our NZ natives have evolved over millions of years to grow in small pockets of soil or up in trees and so these are ideal for vertical gardens, provided you give their roots a good pocket of soil.
At Hanging Gardens, we designed our pockets around the plants requirements and having run numerous trials on plants, we know that a soil depth of around 200mm is fine for most garden plants. In fact almost any plant that will grow in a container will grow in our pockets.
However, plants need more than soil depth. Moisture, nutrients, oxygen and sunlight are also vital for plant growth. Our removable felt pockets further improve plant health by increasing moisture content and aerating the plant roots, something that plastic pots fail to do.
So in a nutshell, not only do our products meet the Living Building Challenge criteria for sustainability, (the only product we know of that does this), but they meet the needs of the plants.
So if you are considering a vertical garden, check the soil depth first. If this is less that 200mm you will be fighting against nature, not something we recommend!