Green roofs are great for smartening up dull and boring arches, arbours, sheds or even a dog kennel!
Alpines are ideal for this as they do not need a huge amount of nutrients and most are fairly drought tolerant. In addition, Alpines do not need huge depths of soil so are perfect for your green roof.
To produce our green roof we constructed an extra frame around the existing roof about 3” deep to keep the growing media in place. We then lined the bottom of the frame with thin plywood and drilled several holes for drainage before attaching to the existing arbour roof.
We laid a thin layer of horticultural sand in the bottom followed by John Innes No. 2 compost.
We then planted up with a mixture of different Alpine leaf and flowers, textures and colours.
We finished it off with a layer of decorative alpine aggregate and watered in well.
After care:
Water only occasionally and deadhead any flowers which have gone over (if needed). In general, green roofs are fairly low maintenance.
The following alpine plants are particularly drought tolerant:-
Arabis, Delosperma, Thyme, Sedums, Sempervivens, Sisyrinchium, Silene, Lewisia.
Please ask a member of staff if you require further assistance or advice.