Roofs & Rambles

Earlier in the year as part of my London leaders pledge I manages to get Lendlease Retail Ltd to install a small green roof on their London HQ. The roof in question was in fact a balcony 30m long and about 1m wide. The roof was installed over a weekend in January by  Garden Lounge - it had to be installed quickly as the main bosses of the company were due to arrive on the Monday from Australia for a major meeting. the UK employers want to show the balcony off.

Their are hundreds/thousands of these balconies across central London, from the Canary Wharf to the City to the West End, from Islington to as far south as Croydon. And we know that most balconies could take vegetation. Over the last year I must have visited 100 buildings in central London with balconies that are currently just paving slabs. So the potential for adding vegetation strips on buildings is immense – giving both tenants/residents/owners not only something visually more appealing to look at but also providing a valuable resource for nature – birds, bees and bugs.

The green roof balcony consists of about 100 -200mm of a commercial substrate provided by greenroofsubstrates and planted with a range of plug plants from British Wildflower Plants. It builds on the idea of the brown roof – native plants on a recycled aggregate base but more formal in appearance.These included Marjoram, Catmint, Agrimony, several sedum species and birdsfoot trefoil. A grasses were planted to give some visual appeal. In the next few months I will return to the site to seed with some annuals and bulbs of chives, muscari and crocii. The bulbs are important as they will provide not only colour but in the spring this year we realised that mining bees were using the flower heads as navigation beacons to their nests.

In the grey concrete jungle of Soho, Regent’s Street, Bloomsbury, and Mayfair a series of balcony roofs could act like hedgerows in the countryside providing a series of green stepping stones for bees and birds, especially, honey bees, bumble bees, black redstarts and house sparrows. Of course it would be better to green the big flat roofs but we must forget that this small spaces around the perimeters of buildings offer a smaller but as important opportunity. But what we must make sure that they are not just ‘dressed’ with exotics grasses and palms, as sop to vegetation but provide some real resource to ensure that nature can crisscross central London and add a bit of colour and life to our cities.