Black walnuts are slow to germinate, sometimes laying in the ground two years before sprouting. But if kept properly they will start by June or July.
For the nursery the ground should be plowed deep and thoroughly pulverized. Plant the nuts 6 to 12 inches apart in rows about 3 feet apart. Put a handful of the sand from the boxes around each walnut. Our soil will appreciate the sand or silt from the drifts along the valley streams, as it has proven to be one of the best fertilizers known. If anyone doubts this let him try a quantity of it on his kitchen garden.
A California Black Walnut near McMinnville
On the Ford place, near the North Yamhill bridge, is one of the finest trees in the county, 33 inches diameter, height 75 feet, spread of branches 60 feet. Bears an abundance of nuts every year. It is 34 years old. The seeds are much used to raise grafting stock.
Nearly all of the black walnut seed produced in the Willamette valley will partake more or less of a mixed or hybrid nature, whether from a California black, Japanese black, or American black. The black walnuts are very susceptible to cross pollinization and the English walnut also, for be it known that
With wandering bees and the sweet May breeze,
That virile tide goes far and wide.
The nut should be planted two or three inches deep. A good authority says to place the nut on its side as it would lay after falling from the tree. If the nut is sprouted make a hole in the well pulverized soil and put the root carefully down into it.