Plant selection is very important, whether for large urban spaces and parklands or residential gardens and rooftops.
As well as taking into account matters like character, purpose, climatic conditions and habitat, species selection must also consider available growing space.
The root system of the Giant Bird of Paradise (Strelitzia nicolai) – seen in the above photo – is aggressive. Planting it in shallow planter boxes or abutting garden paths and underground service conduits is not a good idea.
Generally, small trees planted in a raised garden bed over a slab need at least 1 metre of soil depth. 600mm depth of soil is required as a minimum for shrubs in the same situation.
Even with this principle in mind, it’s best to keep the Giant Bird of Paradise as a planting for substantial open lawns, away from structures. It becomes a much larger specimen than most people realise.