3 TIPS ON ROOFTOP GARDENS
1 Go for simplicity in your containers, decide on your material, decide on the number, keep them all the same.
2 Follow that through with simplicity of planting — don’t try to be too ambitious. Roses won’t grow on a rooftop, wisteria won’t grow three storeys up. Think of the right plant for the right place. Think coastal, think of what will take wind, salt, exposure. Maritime planting is your best bet. The bible is Perfect Plant, Perfect Place by Roy Lancaster. Things like astelias are good, cordylines, flax, generally spiky-shaped things work very well. Eryngium planum or sea holly for colour then, or some nice pretty, soft stuff like osteospermums. Don’t be afraid to go big, weight aside, a pine tree can survive in a big container or try something hardy that can take the exposure.
3 Always have a water source — put a tap on the roof and possibly a sprinkler system and water everything. Wind is very drying.. You can never have too much water, even if it’s on the roof.