Landscaping without harmful invasive plants A guide to plants you can use in place of invasive non-natives Supported by: This guide, produced by the wild plant conservation Landscaping charity Plantlife and the Royal Horticultural Society, can help you choose plants that are without less likely to cause problems to the environment harmful should they escape from your planting area. Even the most careful land managers cannot invasive ensure that their plants do not escape and plants establish in nearby habitats (as berries and seeds may be carried away by birds or the wind), so we hope you will fi nd this helpful. A few popular landscaping plants can cause problems for you / your clients and the environment. These are known as invasive non-native plants. Although they comprise a small Under the Wildlife and Countryside minority of the 70,000 or so plant varieties available, the Act, it is an offence to plant, or cause to damage they can do is extensive and may be irreversible. grow in the wild, a number of invasive ©Trevor Renals ©Trevor non-native plants. Government also has powers to ban the sale of invasive Some invasive non-native plants might be plants. At the time of producing this straightforward for you (or your clients) to keep in booklet there were no sales bans, but check if you can tend to the planted area often, but it is worth checking on the websites An unsuspecting sheep fl ounders in a in the wider countryside, where such management river. Invasive Floating Pennywort can below to fi nd the latest legislation is not feasible, these plants can establish and cause cause water to appear as solid ground. that may be relevant to you: problems for native plants and animals. Trying to Department for Environment get rid of problem plants from natural habitats, Food and Rural Affairs especially sites of nature conservation importance, is www.defra.gov.uk expensive and diffi cult. Often complete eradication Scottish Government of an invasive plant from the wild becomes impossible, www.scotland.gov.uk/invasivespecies and many hundreds of thousands of pounds are spent each year in an effort to limit their spread. These websites provide more information about invasive plants and their management: Other invasive non-native plants will cause problems in their Plantlife amenity setting too, quickly outgrowing their space and www.plantlife.org.uk becoming diffi cult to keep under control. If invasive plants are Royal Horticultural Society used in water features, they can present an additional hazard www.rhs.org.uk as rampant growth can make water appear as solid ground Non-Native Species Secretariat and so be dangerous to unsuspecting children or animals. www.nonnativespecies.org 2 LANDSCAPING WITHOUT HARMFUL INVASIVE PLANTS A PLANTLIFE / RHS GUIDE 3 How to use this guide CONTENTS Our suggested plants are divided into eight sections PAGE Your choice of plant often reflects what you want to do – for example create Groundcover plants 6 a stunning visual display in a public park, or provide a barrier to discourage Naturalising plants & bulbs 8 use of a certain area. Here we try to suggest non-invasive plants for a Architectural plants 11 variety of different landscaping occasions and cultivation conditions. Shrubs 14 Invasive plants have sometimes been used in the past for those difficult areas Climbers / Wall cover 21 of landscaping, like when a bare wall needs to be covered quickly or soil needs to be stabilised. Meanwhile plants for other aspects of landscaping, such as Trees 23 summer bedding, are unlikely to be invasive. This booklet covers those areas Pond & bog garden plants 27 of landscaping where, traditionally, invasive plants have most been used. Plants for wildlife 32 For example, some cotoneasters used for background screening and Cultivation chart & index 36 groundcover are now displaying invasive tendencies in the wild and have been Within each section the recommended plants cover a range of different sites added to Schedule 9 of the Wildlife and Countryside Act. We suggest safer and cultivation requirements. For example, we list shrubs which offer spring or plants you can try instead in the 'Shrubs' and 'Groundcover plants' sections. summer flowers or stunning autumn colours, shrubs that are good for hedging or providing background structure to your borders, and shrubs for sunny or shady spots. Although the plants we suggest shouldn’t cause you undue problems, no matter which plants you use, you/your client will KEY TO need to manage your planted areas at regular intervals. Tolerant of Needs sun Needs alkaline Needs acid Needs Needs SYMBOLS shade conditions conditions drier soils wetter soils Please remember that ALL excess plant matter should be / low light levels disposed of responsibly. The Be Plant Wise website has more information about safe disposal of plant matter: Fast Attractive Attractive Fine Bears Background Low Windbreak Provides growing flowers foliage autumn ornamental structure / barrier shelter/cover www.nonnativespecies.org/beplantwise colours fruit screening / hedge for wildlife BOG Berries Nectar Needs Needs Submerged Floating Marginal / Bog garden for birds source rich soil poor soil aquatic plant aquatic plant emergent plant Credits aquatic plant Images used under Creative Commons licences (1-7): Attribution 2.0 Generic Symbols under each plant highlight particular conditions the plant Attribution-Share Alike 2.0 Generic Attribution-Noncommercial 2.0 Generic requires (for example, wet, dry, acid or alkaline soils, or full sun). Plants Attribution-No Derivative Works 2.0 Generic able to grow in shade are also indicated. A plant with no symbols is able Attribution-Noncommercial-Share Alike 2.0 Generic to cope with a broad range of conditions. The index at the back of this Attribution-Noncommercial-No Derivative Works 2.0 Generic Attribution-Share Alike 2.1 Spain booklet provides full details of each plant’s cultivation tolerances. Images used under GNU Free Documentation License, Version 1.2 Front cover image © Martin McCarthey-iStockphoto Inside layout design by Andrew Evans 4 LANDSCAPING WITHOUT HARMFUL INVASIVE PLANTS A PLANTLIFE / RHS GUIDE 5 Groundcover plants Groundcover plants Erosion control Calluna vulgaris Bergenia cordifolia & hybrids Heather Elephant-ears Variable shrub to 60cm with tiny, densely packed leaves and Robust perennials spreading on thick, branching rhizomes. bell-shaped, often pink fl owers. A great range of cultivars Leaves are large, glossy and paddle-like and purple-tinged selected for fl ower and foliage characters is available. A in winter. The fl owers are usually in shades of pink, borne good option for erosion control at inland sites. on fl eshy stems. Good for sheltered sites. ©Deborah Long/Plantlife ©Deborah ©Uli Lorimer Curator Garden Botanic Brooklyn of Flora Native Ligustrum vulgare Ceratostigma plumbaginoides Wild Privet Hardy Plumbago Hardy semi-evergreen shrub to 3m with narrowly oval, Rhizomatous perennial, woody at the base with wavy- shiny leaves. Spikes of white fl owers are followed by small margined, bright green leaves (to 10cm long) turning red black fruit. in autumn. Produces clusters of bright blue fl owers in late summer. Good for exposed sites. ©Jennifer Snyder ©Jennifer ©ukwildfl owers.com ©ukwildfl Prunus spinosa 'Plena' Leucothoe fontanesiana Double Blackthorn Drooping Laurel Shrub to about 4m with spiny branches and double, white Shrub to 2m or so with arching branches carrying evergreen, fl owers in March and April. leathery, lance-shaped leaves and small white fl owers in spring. Variegated cultivars are available. Needs a sheltered ©Carol Sheppard/RHS ©Carol position. ©Andy Jones ©Andy Rhamnus cathartica Pachysandra terminalis Buckthorn Carpet Box Dense-growing, spiny shrub to 6m with glossy, dark green Evergreen perennial spreading on smooth stems from leaves turning yellow in autumn. Yellowish fl owers in spring which are produced deeply cut, glossy, dark green leaves. are followed by spherical fruit in autumn, red turning Small white fl owers are produced in early summer. black. ©Damon ickr.com/ Taylor www.fl photos/ocean_of_stars ©www.kingsbraegarden.com Ulex europaeus Salix repens var. argentea Gorse Creeping Willow Rounded shrub of dense habit to 2.5m bearing very spiny Prostrate, spreading shrub with oval, silky green leaves that stems which carry bright yellow pea fl owers throughout are silver beneath. Produces yellow catkins in spring. Good much of the year. for exposed, sunny sites. ©Gene Selkov ©Gene ©Barry Phillips/RHS ©Barry 6 LANDSCAPING WITHOUT HARMFUL INVASIVE PLANTS A PLANTLIFE / RHS GUIDE 7 Naturalising plants Groundcover plants & bulbs Sarcococca hookeriana var. humilis Crocus chrysanthus Christmas Box Golden Crocus Low-growing, suckering shrub grown for its glossy, dark Cormous perennial to 5cm with fl owers which can vary in green, narrow leaves and small but fragrant, pink-tinged colour from pale cream to deep yellow, often with a purplish white fl owers produced in winter. The fl owers are followed suffusion on the exterior. by dark, shiny fruit. ©Shihmei Barger ©Shihmei ©Christopher Whitehouse ©Christopher Spring Stachys byzantina Crocus nudifl orus Lamb's-ear Autumn Crocus Spreading perennial to 45cm tall with elliptic leaves to Spreading, cormous perennial to 20cm. Its purple fl owers 10cm which are covered in thick white wool. Small pinkish with a long tube are produced before the narrow leaves. fl owers are carried on woolly stems in summer and autumn. Good for sunny, exposed sites. ©Joan Simon ©Joan ©ukwildfl owers.com ©ukwildfl Autumn Colchicum autumnale Crocus tommasinianus Meadow Saffron Early Crocus Cormous perennial producing copious pink, goblet-shaped Variable cormous perennial to 10cm with pale-striped fl owers (to 15cm), followed by lance-shaped leaves. Double- linear leaves and fl owers which can be pale lilac to deep fl owered cultivars are available. purple. ©Phillippe Bullot ©Phillippe Autumn Spring Dalmeijer ©JManfred Colchicum speciosum Cyclamen coum Giant Meadow Saffron Eastern Sowbread Vigorous, cormous perennial to 18cm with narrow leaves.