A forest garden is a designed agronomic system based on trees, shrubs and perennial plants. These are mixed in such a way as to mimic the structure of a natural forest - the most stable and sustainable type of ecosystem in this climate.

The primary aims for the system are:
· to be biologically sustainable, able to cope with disturbances such as climate change
· it should be productive, yielding a number (often large) of different products
· it should require low maintenance.
The crops which are produced will often include fruits, nuts, edible leaves, spices, medicinal plant products, poles, fibres for tying, basketry materials, honey, fuelwood, fodder, mulches, game, sap products.
Forest gardens (often called home gardens) have been used for millennia in tropical regions, where they still often form a major part of the food producing systems which people rely on, even if they work elsewhere for much of the time. They may also provide useful sources of extra income. Their use is intimately linked with prevailing socio-economic conditions. They are usually small in area, often 0.1-1 hectares (0.25-2.5 acres).

In temperate regions, forest gardens are a more recent innovation, many inspired by Robert Hart’s efforts in Shropshire (UK) over the last 30 years. A major limiting factor for temperate forest gardens in the amount of sunlight available to the lower layers of the garden: in tropical regions, the strong light conditions allow even understorey layers to receive substantial light, whereas in temperate regions this is not usually the case. To compensate for this, understorey layers in temperate forest gardens must be chosen very carefully - there are plenty of plant crops which tolerate shady conditions, but many are not well known. Many of the more common shrub or perennial crops need bright conditions, and it may be necessary to design in more open clearings or glades for such species.

Temperate forest gardens are also usually small in area, from tiny back garden areas up to a hectare (2.5 acres) in size. While food production and land use remain the concern of a minority of landowners and businesses, their use is likely to be limited to ‘alternative’ and organic gardeners and land users.

The key features which contribute to the stability and self-sustaining nature of this system are:
· the large number of species used, giving great diversity
· the careful inclusion of plants which increase fertility, such as nitrogen fixers (eg. Alders [Alnus spp], Broom [Cytisus scoparius], Elaeagnus spp, and shrub lupins [Lupinus arboreus]).
· the use of dynamic accumulators - deep rooting plants which can tap mineral sources deep in the subsoil and raise them into the topsoil layer where they become available to other plants, eg. Coltsfoot [Petasites spp], Comfreys [Symphytum spp], Sorrel [Rumex spp].
· the use of plants specially chosen for their ability to attract predators of common pests, eg umbellifers like tansy.
· the use, where possible, of pest and disease resistant varieties, eg. apples.
· the increasing role of tree cover and leaf litter which improve nutrient cycling and drought resistance.

A forest garden is organised in up to seven ‘layers’ . Within these, the positioning of species depends on many variables, including their requirements for shelter, light, moisture, good/bad companions, mineral requirements, pollination, pest-protection, etc. The layers consist of:
· Canopy trees - the highest layer of trees. May include species such as Oak, Ash, Poplar, Alder, Sweet Chestnut.
· Small trees and large shrubs, mostly planted between and below the canopy trees. May includes Hazel, Cob Nut, Apple, Pear, Plum, Holly, Rowan, Elder, Whitethorn, Birch.
· Shrubs, mostly quite shade tolerant. May include common species like currants [Ribes spp] and berries [Rubus spp], etc
· Herbaceous perennials, several of which are herbs and will also contribute to the ground cover layer by self-seeding or spreading. These may include Comfreys [Symphytum spp], Balm [Melissa officinalis], Mints [Mentha spp], Sage [Salvia officinalis], and Tansy [Tanacetum vulgare].
· Ground covers, mostly creeping carpeting plants which will form a living mulch for the ‘forest floor’. Some may be herbaceous perennials (see above
· Climbers and vines. These are generally late additions to the garden, since they obviously need sturdy trees to climb up.
· The final ‘layer’ is the root zone or rhizosphere. Any design should take account of different rooting habits and requirements of different species, even if root crops are not grown much. Various beneficial fungi can also be introduced into this layer.

BENEFITS:
· A long-term biologically sustainable system for growing food & other products for a household
Once established, little work is needed to maintain