A fundamental principle of the Campaign for Real Farming is to use British produce as far as possible and import only those foods that we cannot grow here. Walnuts challenge this principle in that we can grow them, but mostly don’t, at least not commercially.
As the country steps up its tree planting to help combat climate change could walnut trees feature in this planting and at the same time improve our food security?
Almost 40% of the worldwide export in walnuts comes from California, with the UK being their 5th largest market. Walnuts are rich plant source of Omega 3, and so of special importance in vegan and vegetarian diets, although valued by all for their health-giving antioxidants. The UK market looks likely to continue to expand whilst repeated drought and wildfires in California throws into question walnut production there. However, Californian walnuts are sold in supermarkets for less than half the price of the rarely found home produced walnut. The CBI provides market information for potential new entrants, although personally I would hesitate to recommend growing them from a purely commercial standpoint, although the value of walnut wood is apparently good.
My enthusiasm for English walnuts stems from their culinary attributes. Californian walnuts are what I had eaten for most of my life until a friend brought a sack back from France. These walnuts were from Grenoble, the first fruit to receive the French quality symbol that went on to become known as “Protected Designation of Origen”. Périgord was later also awarded PDO status and is probably the better-known region for French walnuts. The ones my friend had brought home from Grenoble were a complete revelation to me. Finally, I understood the fuss about walnuts and from then on Californian just wouldn’t do.
The following year I saw “wet-walnuts” for sale in Somerset and, despite their unappetising appearance, leapt to buy them. Walnuts are “wet” when they first ripen in September and you could literally squeeze oil from them by hand. The shells are blacker at this stage, so they don’t look particularly appetising. When you crack them open the skin is still soft enough that you can peel it away and, as the skin is the most bitter part, you may wish to do this. Wet walnuts are ideal for pounding to make a sauce – for example to serve with pasta or fish. However, the nuts won’t store for long unless you dry them. Walnut oil is very unstable, so even when dried they are best eaten within a few months. The freshness is probably what made my first taste of Grenoble walnuts so wonderful, and I am now firmly wedded to the seasonal aspect of the nut. If I see them listed amongst the ingredients of an otherwise clearly summer dish it really jars with me, so whilst some people might see them as a year-round provider of essential nutrients, for me they shout Autumn and Winter.
In addition to the over-riding importance of freshness, the question of the suitability of the trees to a particular area definitely intrigues me. I accept that the regions of Périgord and Grenoble in France are ideally suited to growing walnuts, but what I can’t say, at this time, is whether we have similarly suitable areas in the UK.
Walnut trees are slow growing but long lived. They require plenty of space and the land beneath becomes fairly barren owing to the chemical juglone produced by the roots, so it is often planted on the periphery in agroforestry. It takes 10 years for a tree to start producing a decent number of nuts, and even then, nut production is fairly hit and miss. No-one seems to be quite able to explain why some trees do well and others do not. There is an old rhyme that hints at this problem although containing no sensible advice:
A woman, a dog and a walnut tree,
The more you beat them the better they be.
Certainly, walnut trees are unlikely to produce nuts consistently in the northern part of this country and locally in Somerset I have found them to be more forthcoming on the warmer southern flank of the Mendips than on the north, although even here I know ancient trees producing well and others that do not.
In the late 17th century Surrey was at the heart of walnut growing in the UK. This came about when John Evelyn was asked by the Royal Society to draw attention to the damage done to England’s wooded estates during the English Interregnum and to encourage reforestation. His findings were published in 1664 under the title “Sylva or a discourse on forest trees and the propagation of timber in His Majesty’s dominions”. He championed the growth of walnut plantations on several family estates, including his own around Godstone, and elsewhere in Surrey, notably at Leatherhead and Carshalton. The walnut tree was clearly suited to the Surrey soil, although whether it was especially so or just the result of many large estates being found in proximity to the court is not certain. Whilst some people are lucky enough to have their own walnut tree, because of the space required they have always been more associated with large properties. Their prestigious status is evident from the number of times their presence at a property, even as a single tree, is reflected in the house name.
However, Evelyn’s project came to an abrupt end just two years after his death, when the bitter winter of 1708 destroyed most walnut trees in northern Europe.
Trees were replanted, but commercially it became their timber that produced the greatest value. Walnut wood is used in cabinet making, marquetry and for gun stocks. Many trees were felled for this later purpose for the Napoleonic Wars in the 19th century. The same thing happened again in the Crimean War to the extent that one Birmingham arms maker had to transfer his operations to Turin where the supply of walnut wood was more assured.
And so, we find the current position in Britain today is that walnut trees are mainly grown in isolation, if the garden is large enough, an ever-rarer occurrence; or the remnants of large estate plantings might be found around its margins. Bossington, part of the Holnicote on Exmoor, provides a great example of the latter. You can find seven walnuts trees of varying ages around the green and more along nearby roadsides. The once famous giant tree which had dwarfed a cottage beside the green was felled in the 1950s.
A more recent estate planting exists near Glastonbury. Roger Saul decided to replant walnut trees at Sharpham Park when he discovered evidence of them having been grown there when it was a monastery. 300 trees were planted in 2004 and 12 years later they were producing enough nuts to sell. British walnuts (and Sharpham Park’s are Organic) sell for about £20 a kilo. You can also buy British walnuts online from Potash Farm in Kent.
As yet, few people seem to appreciate the qualities of British walnuts enough to create much demand, although I am convinced that when they taste them, especially the young wet walnuts, they will never look back. The most widely planted variety of walnut tree in the UK is Broadview, but If you are thinking of planting there are many modern hybrids available to suit specific requirements – see the websites below.
I do now have my own walnut tree, but don’t get many nuts from it. Squirrels are the main problem here. The tree does produce a decent crop, but the squirrels take the vast majority. In an effort to beat them to it, I have harvested some of the nuts when “green”, in early July, and pickled them. Pickled Walnuts are the only culinary use for walnuts for which the British have gained any renown, although we are not by any stretch, the only culture to use this method to preserve them. One researcher identified more than 60 distinct recipes for pickled walnuts from countries as diverse as Australia, Britain, Canada, China, France, Germany, Greece, Holland, India, Italy, Mexico, New Zealand, Portugal, Russia and Ukraine. Two features stood out that distinguish “British Pickled Walnuts” (those originating in British speaking countries): – none of them include garlic and all of them include sugar of some type. About half of the British recipes include ginger.
The use of pickled walnuts varies is as variable as the recipes, but here in Britain they are almost exclusively used as an accompaniment for cold or grilled meats. I have given Dr Kitchener’s recipe for “Wow-Wow Sauce” which dates back to 1817 as an example of the particularly British use of pickled walnuts.
You can see my walnut recipes here.
A Passion For Trees: The Legacy Of John Evelyn, by Maggie Campbell-Culver 2006
Potast Farm – www.kentishcobnuts.com
https://www.permaculture.co.uk/articles/why-you-should-grow-walnuts-juglans-regia includes a link to companion crops that seem unaffected by juglone.