Green roof suitable for a Coastal Green A green roof is a roof or deck onto which vegetation is roof intentionally grown or habitats for wildlife are Scientific Name Common Name established. Achillea millefolium Common yarrow There are two main types of green roof: Aira caryophyllea Mouse grass Aira praecox Early hair grass… • Intensive Kidney vetch Typically have deeper substrates (>200 mm) capable Arenaria serpyllifolia Thyme-leaved sandwort of supporting shrubs and trees and generally they Thrift have the appearance of roof gardens. They will Bromus hordeaceus Soft brome require significant management and maintenance in Centaurium erythraea Common centaury terms of irrigation. Cerastium diffusum Sea mouse ear • Extensive Cochlearia danica Danish scurvygrass Green roofs typically have a shallower substrate Cochlearia officinalis Common scurvygrass layer (<150 mm), support low-growing, drought- Sedum roofs in the National Park Erodium cicutarium Common stork’s bill… tolerant and require low maintenance. Euphorbia portlandica Portland spurge Extensive roofs are the most common type. It is advised that sedum-only roofs are avoided in the Festuca ovina Sheep’s fescue… National Park, due to the limited number of native sedum Festuca rubra agg Red fescue… Benefits of a green roof species. Galium verum Lady’s bedstraw… Hieracium pilosella Mouse-ear hawkweed A green roof will provide benefits such as: There are only two species of sedum native to montana Sheep’s bit scabious • Green stepping stones for wildlife Pembrokeshire that are suitable for inclusion in a green Koeleria macrantha Crested hair grass • Water storage - SuDs* roof: Leontodon taraxicoides Lesser hawkbit • Sound dampening • Sedum acre - Goldmoss stonecrop Lotus corniculatus Bird’s-foot trefoil • Production of oxygen • Sedum anglicum - English stonecrop Matricaria maritima Sea mayweed • Absorbing air pollutants, dust and CO2 Myosotis ramosissima Early forget-me-not • Visual aesthetics to sites The implementation of a sedum roof with only two species Plantago coronopus Buck’s horn plantain • Insulation (increased thermal mass) would result in a roof with limited ecological and aesthetic value Ornithopus perpusillus Bird's-foot Plantago lanceolata Ribwort plantain.. *Sustainable Drainage Solution The use of other sedums (including garden varieties) for a Plantago maritima Sea plantain green roof in Pembrokeshire would not be acceptable as Sagina apetala Annual pearlwort… they can become invasive, putting native species at risk. Sagina maritima Sea pearlwort Sanguisorba minor Salad burnet… Protected habitats Scilla verna Spring quill Maritime, Cliff and Crevice communities are abundant Sedum acre Biting stonecrop along our coastline; often listed as features of designated Sedum anglicum English stonecrop sites such as: Silene maritima Sea campion Spergularia rupicola Rock sea spurrey • Special Areas for Conservation (SAC) Thymus praecox Wild thyme… • Sites of Special Scientific Interest (SSSI) Trifolium arvense Hare’s-foot clover Once a has escaped into the wild it can be difficult Veronica arvensis Wall speedwell… and costly to eradicate. • ‘…’ Represents species with other common names • Species listed - National Vegetation Classification Maritime In many cases eradication is impossible and can have a Therophyte* community MC5 long term impact on the ecology of protected and special • *Therophyte - Any plant which survives unfavourable conditions in habitats. the form of seeds only National Park green roof preferences Green Roof The use of native species and the mimicking of natural habitats helps to provide the maximum benefits for the Guidance wildlife and landscape of the National Park. in the To encourage these benefits the more typical choices for a green roof would be: Pembrokeshire Coast National Park

Pembrokeshire ‘coastal’ roof This type of roof will comprise plants which are highly adapted to coastal conditions and as a result will tolerate drought, high levels of exposure and salt-laden winds, making them ideal for our environment. Some of these plants also undergo colour changes during times of drought that provides additional visual interest. A species list of suitable plants is provided in the leaflet. Further information External guidance documents: UK native wildflower roof • ‘The Green Roof Code’ by GRO • ‘Guide to DIY Green Roofs’ by GRO These normally comprise a mix of flowers and grasses • ‘Creating Green Roofs for Invertebrates’ by Buglife which are native to the UK and are often available from • www.pembrokeshirecoast.wales major suppliers as plugs, seeds or as a ‘ready-to-roll’* option. Please note: Ready-to-roll options can sometimes include non-native species which can be unsuitable. This leaflet is intended to be a helpful and simple guide These types of product would only be considered in and should not be regarded as a full interpretation of a inland locations following approval of the species green roof implementation. included. If you have any doubts regarding possible planning requirements or other questions, please contact: • *’Ready to roll’ – This is a complete seed stock and substrate layer product sold in the form of a mat / blanket / carpet Development Management Pembrokeshire Coast National Park Authority Llanion Park Pembroke Dock Pembrokeshire SA72 6DY

Telephone: 01646 624800 Email: [email protected]

LANDSCAPE LEAFLET 1 Pembrokeshire Coast National Park Authority 2019