The selection of the correct tree and shrub species – fitting to the location in terms of scale and colour, climatic requirements and growth habits – can be as imperative to the success of a development as the detailing of the buildings and the floor space between them.

Trees and shrubs suitable for 'private space' often appear mean and inappropriate when planted in public spaces, and the provision of larger trees or fast-growing vegetation in private space can quickly overwhelm or dominate.

It is possible to design planting schemes to benefit the ageing population and those with dementia, and this should be considered from the outset of any new development. Such schemes may not be readily identifiable or appear different to other parts of the population – being viewed as regular landscaping – but to older people or those with dementia they can offer significant benefits to health and wellbeing. They can also help to reduce the need for future adaptation.

As a general rule, deciduous species should be chosen, as they provide visual interest throughout the year, allowing light and air to penetrate to ground level during winter. Evergreens, however, can be used to conceal unsightly features, or to act as a focal point. Furthermore, they can be used to create natural forms of enclosure, and to distinguish between public and private space. This is desirable from a general urban design perspective, but is also important for people with dementia, who can see more ‘solid’ or ‘hard’ types of enclosure as oppressive or imprisoning.

In publicly accessible places, trees should have trunks clear of branches or under-planting to avoid providing cover for anti-social behaviour.

The list of plants below is provided for illustrative purposes and as a guide to good practice. The list is not intended to preclude the use of different species or to provide a ready-made planting scheme but to provide an example of species that may be appropriate in different situations. In the preparation of planting schemes, advice from appropriately qualified and experienced people is essential.

Type of planting	Plant species	Comments
Planting in verge (ground cover)	Ceanothus thyrsiflorus repens  Chaenomeles (Quince) Cotoneaster dammeri (and some cultivars)*  Hedera helix 'hibernica' (Ivy)  Hypericum calycinum (St John's Wort) Lonicera pileata  Pachysandra terminalis (London Pride) Pyracantha (spreading cultivars) (Firethorn) Symphoricarpos (shorter-growing forms) (Snowberry) Cornus sanguinea (Dogwood)	* other Cotoneasters are invasive and are covered by Schedule 9 of WACA
Avenue and street tree-planting	Liquidambar Styracifula (large) Platanus Hispanica (London Plane) large Quercus cerris (Turkey Oak) large Tilia cordata (Small-leaved Lime) large Prunus padus (Bird Cherry) medium Robinia psuedoacacia (False Acacia) medium Corylus colurna (Turkish Hazel) small Crateagus monogyna(Hawthorn) small Malus tschonoskii (Ornamental Apple and other varieties) small Pyrus chanticleer (Ornamental Pear) small Sorbus aucuparia (Rowan) small Carpinus betulus (Horbeam) medium
Hedges to front boundary	Carpinus betulus (Hornbeam) Corylus avellana (Hazel) Crataegus monogyna (Hawthorn) Fagus sylvatica (Beech) Ilex aquifolium (Holly) Ligustrum ovalifolium (Privet) Prunus lusitanica (Portuguese Laurel) Taxus baccata (Yew)
Trees for structural planting and wildlife corridors	Acer campestre (Field Maple) medium Quercus robur (English Oak) large Quercus ilex (Holm Oak) large Tilia platyphyllos (Large-leaved Lime) large Malus species (Crab Apple) Prunus avium (Wild Cherry) medium	Where there is more room such as on rear boundaries, within open spaces or close to pedestrian routes, larger species can be used to form a permanent landscape structure within development.

Root Barriers

Avenue tree-planting or trees in urban spaces may cause problems to the foundations of nearby buildings due to root spread. It is therefore recommended that a root barrier be installed between trees and nearby buildings in those cases where the face of the building would lie within the root spread at the eventual maturity of the tree. Whether a root barrier is necessary in order to protect underground services will depend on the depth of the services as well as their proximity to the trees. It is recommended to seek advice from a professional Arboriculturist. 

The Ageing Population and People with Dementia

In order to ensure that the needs of the ageing population and those with dementia are met, landscaping and amenity spaces should provide for multi-sensory stimulation (sight, touch, smell, sound and taste) while taking into account a range of sensory and mobility issues.

Trees should provide both shade and shelter, but should not appear too dark; deciduous trees such as birch and cherry provide light cover. Evergreen trees and shrubs can provide enclosure and screening without creating the impression of oppression or imprisonment.

Herbs, lavender and other scented plants release fragrance when touched or brushed.  These should be planted at a variety of heights and locations to ensure that people of all ages and levels of mobility can benefit from them, both in terms of touch and smell.

Herbs, fruit, vegetables and salad can provide both the ‘edible’ experience (taste) and opportunities for outdoor activity and interaction. Other plants should be non-poisonous to avoid any confusion.

Spiky and thorny plants can be included to provide some structure and architectural attributes to landscaped and amenity spaces, but these should be located in non-hazardous places, such as at the rear of borders.

Ornamental grasses can be visually stimulating, through their movement in the wind.  A variety of colours and shades is also appropriate, and combinations can provide specific zones within a space. Hot, vibrant colours can evoke a sense of liveliness while cool, pastel colours can be relaxing and therapeutic.

A mix of deciduous and evergreen plants together with plants that flower throughout the year can ensure that amenity spaces are stimulating, inviting places all year round. This applies both to the experience of physically being in the space and the experience of viewing it from inside a dwelling.