Vertical gardens are great for façades, insulation and to add a bit of greenery to a home or office. But the problem with them is that they require a lot of maintenance and power to flourish. Well, that could be a thing of the past. The firm Treebox, which specializes in urban greening, has created a vertical garden, which is entirely self-sustaining. It needs no power and gets all its water needs taken care of by rainwater, hence its name—Rain Garden.

The vertical garden pictured above is located in London. The rainwater needed to irrigate it is collected in tanks, which are hidden beneath the greenery. Instead of a pressurized irrigation system typically used in such gardens, this one uses a “wicking rope” to water the plants. This works by allowing the plants to absorb the water they need through a capillary action.

The plants are therefore irrigated in a controlled way so that they do not get too much water too fast. The system is also capable of reducing the water supply to the plants when there is high rainfall, while a tank filled to capacity can sustain the garden for up to six months.

This Rain Garden is an excellent solution for use in areas where servicing them is not easy. The gardens are planted with mostly evergreens, such as ferns and mosses, or more precisely Asplenium, Polystichum, Carex Elata, Sarcococca and Geranium.


The Rain Garden in the UK was installed about 2 years ago as part of the Drain London sustainable urban drainage program. It has proven to be so successful, that they recently extended it to measure 96 feet (30 m) meaning they tripled its original length. Hopefully more urban areas will consider adopting this approach to drainage in the near future.