The forest garden at Dartington was created over the last 24 years by Martin Crawford of the Agroforestry Research Trust (ART). A forest garden uses useful plants to mimic the layers of a natural woodland to create a stable ecosystem. It is a popular theme in temperate climate permaculture. The picture above illustrates the forest garden layers at the edge of the garden by the carpark, including unseen roots (of mashua and japanese yam). The timing of our holiday was timed around the ability to participate on one of the tours that Martin runs periodically through the year. It also had to be outside of the peak season on Skye. I didn’t always catch the latin names of the plants during the tour, so in general I have used the common names that Martin used. When he did give the latin names I realise that I have probably been mispronouncing them all these years, having mainly learnt them from books!
The canopy layer is mainly made up of italian alder trees which have had their lower branches removed in order to let more light through. Even so the garden was much more shady than Sagara’s garden, feeling much more like a woodland with clearings, rather than a field with trees. Martin has not used soil landscaping to create microclimates, explaining that as his plot sloped south and was sheltered at the start by a wood to the west it had not been necessary.
Having already visited Sagara’s garden many of the plants were familiar to us already, although Martin’s trees were considerably bigger. He stressed the importance of plotting the area and planting spacing based on mature tree sizes since all the layers will require light to be productive. Clearings form suntraps that enable Martin to grow even quite tender fruit like persimmon. It has been a hot year this summer following a cold winter, and many of the fruit are a couple of weeks early, and some that don’t always ripen are doing well.
Much of the ground under the trees was clear of plants, being covered by leaf mulch. In the spring there are more bulbs in growth such as wild garlic. The main spreading ground cover Martin had visible at the time we came was false strawberry. This has a yellow flower, and although it does set some little red strawberry like fruit, they are disappointingly tasteless. The false strawberry has the advantage of being evergreen, so protecting the soil year round. Other shade loving ground covers included Hosta, and fiddlehead fern (Matteuccia struthiopteris) both of which I fancy growing. There was also mint, ground covering raspberries and japanese wineberry, with comfrey and turkish rocket in the sunny spots. Martin said that turkish rocket was one of the few plants that could happily compete with comfrey. Other ground layer plants included more of the japanese spring vegetables, solomons seal and japanese ginger, which is harvested by cutting the growing shoots rather than digging it up. The main weed that Martin gets seeding in the garden is Ash trees. Sadly this may not be the case for much longer, since the ash dieback has spread to the county.
Martin talked about the importance of soil mycellium (fungal networks) in sharing the nutrients about the wood. They also can spread warnings amongst the plants. If one plant is stressed or attacked by pests it releases chemicals that, transmitted by the mycellium, stimulate other plants to increase their own chemical defences. Martin said that generally it isn’t neccessary to innoculate the soil. As long as it wasn’t disturbed, the fungi would already be in the soil, particularly close to existing trees. It is however possible to buy edible fungi spawn to encourage more edible fungi in your forest garden, and he also showed us an oyster mushroom log that he had stimulated to fruit before we came. It is possible to have a number of logs that are ready to produce mushrooms and trigger them in turn so as to have a continuous supply of mushrooms. I have tried unsuccessfully to grow mushrooms on newspaper ‘logs’. I think that because I wrapped them in bin liners to keep them damp the spawn was suffocated, so I may have another go.
There are a number of trees that Martin grows for leaf crops, either as salad greens or as cooked vegetables. One that I recently got is Toona sinensis or toon tree (visible as tall shrub layer in top photo). This has leaves that when young, are eaten as a vegetable in china. We tried a little leaf, and it tastes rather like an aromatic onion. Salad leaves include small leaved lime (tilia cordata), which has quite pleasant mild tasting young leaves, beech (fagus sylvatica), which I always find a bit tough even when young, and white mulberry. We tried the leaves of the latter, and again I found it a bit tough, although not unpleasant in flavour. It may have been better when younger, or cooked though. Martin pollards all these trees to keep a supply of young leaves in easy reach, but out of reach of browsing deer.
Other interesting shrubs included relatives of the common bog myrtle, which itself has edible leaves used like bay leaves. The wax myrtle has similar uses for the leaves and also the berries have a waxy coating that can be melted off and used in candles and sealing etc. These are nitrogen fixing in boggy ground, so may be ideal in certain areas of my field! I do have the wax myrtle on my list of ‘wants’, although I am having difficulty in getting seed to germinate. You need male and female plants to set berries. I do have some bog myrtle down by the river, although am not sure whether they are male or female. It is useful if caught by midges, since they don’t like it’s aromatic foliage.
Another nitrogen fixing tree is the judas tree. We did see this at EDFG, but didn’t know what it was. Martin had a good sized tree which I asked about. Prior to arriving at Dartington, we saw another in a green space where we had our picnic lunch. It has distinctive heart shaped leaves. Apparently the flowers are edible and come out before any of the foliage on bare branches. I collected some seedpods from the one we saw at our picnic spot, so I may see if I can get some seed to germinate.
We tried some sechuan pepper seeds, they are very peppery and made my lips and tongue numb for a few minutes. Apparently this doesn’t happen with the dried fruit, which can be mixed with salt and ground together for salt and pepper seasoning. I quite fancy trying to grow this. Apparently there are lots of similar shrubs all called sechuan pepper, so I’ll have to check with Martin the one that he uses! Nepalese pepper is quite similar, but ripens later, so is less likely to be suitable on Skye.
An interesting edible that I didn’t remember from my reading is the Trachycarpus ‘palm tree’. Apparently it has huge flowers that can be used like cauliflower. I know this will grow locally here on Skye, and I did have a couple but gave them away since I wasn’t sure where to put them. I sort of regret that now!
Trees that I forgot to mention from EDFG that we also saw in the Dartington garden were alternative haws. There are several plants closely related to our native hawthorne that have bigger and nicer berries. I have one, Crataegus arnoldiana, although it hasn’t flowered for me yet. Martin had several haws which we were able to sample the fruit of. I have ordered seeds of lots of different varieties from the ART to try and grow this year. If I find one that does well for me, I may be able to graft it on to the common hawthornes.
There was a clear area under a huge pine tree that Martin sometimes uses as an outdoor classroom. He says it is important not to forget the people in the garden and have a space for them to use. It was impressive that the huge tree had been grown by Martin from seed (as were most of the more unusual trees we saw). He talked about harvesting resin from the tree and the uses it has (turpentine, rosin etc.).
A pond area was also planted with edible plants: Arrowhead (Sagittaria latifolia – has edible tubers), mint (needs no explanation) and Houttuynia Cordata. This last we tried a leaf of. It has a strange fishy orange taste that I wasn’t too keen on but some others liked. It is a popular vegetable with fish in china. A little research reveals that in some climates it can be invasive, but I don’t think I’ll bother with it, although I do fancy developing an edible pond/bog area below the barn!
In summary, this was a truly inspirational visit again. Such a treat for me to meet Martin Crawford who has done so much for the development of agroforestry in the UK and internationally.