PLANT MATERIAL:

Plant material should be chosen to withstand the unique growing conditions on Green Roofs. Climate and local roof conditions play a large role in the choice of plant material. This is not to say that aesthetics are unimportant. For this reason it is recommended to plant a mix of plant material with ground covers in combination with single small upright perennials which are suited to the hardiness zone, rain fall, sun, shade and wind conditions of the microclimate, specific to the roof under consideration. There are a wide variety of sedums, herbs and grasses that meet these requirements.

Traditionally, sedums have been the backbone of the extensive Green Roof plantings because they have the properties best suited to these growing conditions. They come in a wide range of leaf and flower colours and they root quickly. In general planting should be done between spring and early fall to give the plant material ample time to settle and take root, which is important to survival for the winter months.

There are a couple of methods to plant an (Extensive) Green Roof , which are: Pre-cultivated vegetation-mats, root plants or plug-plants, sedum-cuttings and seed sowing, depending on the budget and the design requirements.

Special plantings can be designed to increase biodiversity if that is a priority.