In a densely built-up borough like Tower Hamlets, greening our built environment is an important component of biodiversity conservation. This can include green roofs and walls, providing places for nesting birds and roosting bats in or on buildings, using sustainable urban drainage systems to provide wetland habitats, and a variety of other design and landscape features. The London Biodiversity Partnership has published guidance on Design for Biodiversity.
The best landscaping for biodiversity usually involves creating natural-type habitats, such as meadows, woodlands and ponds, using locally native species. However, there are many places where this is not appropriate, and something more formal is required. Formal landscapes can still benefit wildlife if they include plants that provide nectar or fruit, or places to shelter and nest. Local bee expert Mark Patterson of Api:Cultural has produced a list of the best garden plants for bees, and a matrix showing the flowering times and colours of good plants for pollinators. Further lists of good nectar plants for pollinators are available on the Royal Horticultural Society and London Beekeepers’ Association websites. The Royal Horticultural Society also has a list of night-scented plants which will attract moths and other nocturnal insects, and hence provide food for bats. The Wild About Gardens website provides information on which plants will benefit wildlife in any situation from a meadow to a herbaceous border, and is endorsed by the Wildlife Trusts and the Royal Horticultural Society.
Right Place, Right Tree
The Forestry Commission and Mayor of London have published advice on which trees to plant to provide a variety of benefits, taking account of climate change predictions. The Right Trees for a Changing Climate database is available to anyone who registers (registration is free).
Planning policies in the London Plan (policy 5.11) and Tower Hamlets Council’s Core Strategy (policy SP04) and Managing Development Document (policy DM11) promote green roofs in new developments. The Mayor of London has published a technical report on the benefits of various types of green roofs in support of the London Plan policy. This technical report can be downloaded here (PDF 2.6MB). The Green Roof Organisation, representing the green roof industry, has published a Code of Practice, the Green Roof Code, which provides a lot of useful information and best practice guidance.
Some types of green roof are better for biodiversity than others. The commonest type of green roof in new developments in Tower Hamlets is a sedum mat, like the one at Canary Wharf in the photo above. While these roofs provide some habitat for wildlife, there are far more biodiverse approaches to green roofs. Buglife has published best practice guidance on creating green roofs for invertebrates (PDF 6MB). This is widely regarded as the best current guide to creating biodiverse green roofs.
Nesting and roosting features for birds and bats
Boxes and bricks for nesting birds and roosting bats are widely available from a number of suppliers.
The London Biodiversity Partnership has published guidance on providing bat roosts and peregrine nest sites in new development. The Swift Conservation website contains a wealth of information about providing homes for swifts in new development, and contains links to suppliers of swift boxes and bricks. This leaflet provides more information on boxes and bricks for swifts, and here is a design for an easy-to-build swift box.