Walnuts were highly valued as a timber tree centuries ago, but 2015 was a good year in Scotland for the nuts too…our neighbours ‘Buccaneer’’ produced a good crop of nuts. So I thought I would do a bit of research on varieties and their relative merits. Maybe we should be growing more in Scotland? They can even be grown as a hedgerow system, not unlike many apple orchards around the world today.
I know of a few very big old walnut trees in Scotland, so I imagine a need for a less vigorous cultivar would be very useful for most of us. My neighbour’s tree is 8 years old and already romping away at about 12m and growing a meter a year!
It is presumably self-fertile as there are no others in the area.
We have a few seed sown trees for sale here at the nursery.
The Common walnut is Juglans regia, the black walnut, and is native to Persia, Juglans nigra. Is native to North America. Both can produce edible nuts.
The fruits are actually a drupe not a nut! You can expect cropping from 3 to 5 years from many varieties.
Romania is the biggest producer with production of up to 23 tonnes per hectare, but there’s a wide distribution of production from China, through India, Iran, France, and increasing production in Morocco.
( see: http://www.highatlasfoundation.org/).
Over 30 varieties are listed in Wikipaedia (https://en.wikipedia.org/wiki/Walnut ), but here are the most commonly available varieties in UK and abroad:
Buccaneer – A self-fertile Dutch round nut variety. Good for pickling. Upright tree.
Fernor – A new precocious flowering French variety.
Franquette – an old variety, a tip bearer! Doesn’t need much pruning.
Rond De Montignac – another old French variety with smaller nuts and late to leaf out.
Broadview – supposedly less vigorous than others.. self-fertile, precocious, and reputedly frost hardy. From Canada.
Saturn – A Czech variety 1971
Rita – From Carpathians, a smaller tree with thin -shelled nuts.
Lara- a commercial French variety, compact, needs a pollinator
There are many varieties more in France and around the world!
The RHS suggest taking out the central leader if you want to keep the trees in check. Also avoid pot bound plants as the tap -root will be damaged and they hate transplanting so don’t move them once they are planted.
Do not plant them near to apples as the roots exhibit allelopathy – preventing other trees growing. Most need at least 7m spacing between trees.
Grey squirrels, leaf gall, anthracnose and Codlin moth can all be problems with Walnut trees.
So is there anyone in Scotland interested in growing and trialling varieties for a commercial crop of walnuts, i.e. a hedge of them?