EXTENSIVE ROOF GARDENS
Extensive roof gardens require little maintenance, yet they provide the comfort of a garden.
Such gardens are usually arranged in inaccessible places or places where we want to be ‘green’ and visually pleasing, but they are not used on an active basis.
Due to the limited substrate thickness amounting to 8-12 (15) cm, the choice of plants that can be planted is limited. Meaning, for extensive roof gardens, the many species of succulents (most often Sedum sp.) are most often used, which includes meadow grass, herbal plants and moss.
Maintaining these gardens is simple, there is no need to regularly water, weed, or maintain the plants, and most often the plants are left at the ‘mercy’ of natural conditions.
BUILDING EXTENSIVE ROOF GARDENS
Water insulation requires protective geotextile, and accumulating drainage troughs made of polystyrene are placed on it.
Next, filter geotextile is placed over the troughs and then a specially prepared mixture of substrate for planting seedlings is brought in. The substrate is usually delivered in large bags, which are placed on the roof by a crane due to hindered access. A settled substrate layer of 8-12 cm is sufficient for an extensive roof garden.
The levelling out the substrate is followed by planting the plants, and in this case a few types of broadleaf stonecrop (Sedum sp.). The plants are planted in accordance with the project, and the amount of plants per square meter depends on the size of the plants and the desired effect (we recommend 25-35 pcs/m2).
In the first few months after planting, the plants should be watered occasionally, whereas later on watering won’t be necessary.