Fruit and Nut
Fruit and nut trees and forest gardening
Forest gardening is a system is managing woodlands or forests to provide useful yields of fuel, food, and other materials. The emphasis is often on systems that can be maintained in equilibrium with relatively little maintenance. In theory, at least, the combined outputs of the forest exceed what can be grown if each of the outputs are produced separately. Equally, or perhaps more importantly, the system can be maintained with minimal inputs of nutrients - the idea being that the losses to the system through harvesting are replaced through carbon and nitrogen fixing and the extraction of nutrients from the soil and subsoil by the forest microorganisms and plants.
The greater the rate of harvest of food, fuel or other materials, the greater the requirement to fix or extract replacement nutrients.
Much has been written elsewhere about the potential of fruit and nut crops in forest gardens. However, most of the literature has been written by people working in climates very different to Ireland's. In hot dry climates, growing food crops in forest gardens makes perfect sense. In cool wet climates, it is unrealistic.
Our experience of 26 years of growing fruit and nut trees in the cool wet climate of west Mayo (and a further 8 years in other parts of Ireland) is that fruit and nut yields in forest gardens tend to be extremely low - often as little as five to ten percent of the yield that might reasonably be expected in a more conventional orchard layout . The bottom line is that domestic cultivars of fruit and nut, selected over hundreds of years to perform best in open orchard situations, and in almost all cases developed in climates drier and sunnier than Ireland's, generally do extremely poorly in the damp and shaded conditions in woodlands.
This is partly due to the much lower levels of light and sunshine (which in Ireland are low to start with), but also to the much greater risk of disease in the more humid and less-ventilated conditions. These are issues rarely discussed in the literature on the subject. Major fruit and nut diseases such as canker, scab and blight are much bigger problems when plant ventilation is poor. Although much of the appeal of growing food crops in forest gardens is the idea it is maintenance free and that crops can be produced with little or no horticultural experience or knowledge, in reality it is much more likely to be the complete opposite: that a high degree of tree expertise and considerable maintenance work will be needed to achieve any sort of yield at all.
Our general advice for people intending to plant fruit or nut trees in forest gardens is to not expect much in the way of crops! Where fruiting trees are desirable, the best results will be achieved with native woodland species (for example the wild cherry) or woodland species native to other cool temperate regions. Where domesticated cultivars are desired, they should be selected from varieties known to have the highest resistance to disease, and also those most tolerant of shade. In general, domesticated cultivars of plum, pear and cherry, and most eating apples are not suitable. With the notable exception of the edible evergreen oaks, nut species are not recommended. However, the odds of success can be improved by planting the trees on the sunnier and more open south-facing fringes of woodland, or in more open situations, for example in spacious clearings within the wood.
The species that will do best in forest garden suitations are the wild fruits and berries that are indigenous to cool, wet forest environments.
For the grower looking for more than the sparce and sporadic yields offered by the forest garden, our advice is to plant fruit or nut trees in a more conventional orchard situation, but to use the tree cover offered by an adjacent forest garden or woodland to provide shelter. The shelter will be most effective on the northwest, west and southwest. Shelter on the south side is also useful, but shelter trees should be kept low in order not to block out light. Shelter from the north is less critical, but can help raise the temperature within the orchard.
There should be a gap of between seven and twelve metres between the shelter belt and the nearest orchard trees. In the case of hedges that can be kept trimmed at orchard height, the distance can be reduced to five to seven metes, smallest on the north side.
For further advice, including choice of species, please contact us.