There are a few ways for the reproduction of the olive tree. The tree that gives us the liquid gold, the olive oil.
One way is by the seed. We understand that a grown olive tree has to be grafted, because if it doesn’t, it is going to remain a wild tree, producing a poor and small fruit. We also should understand that by using the seed, the tree is stronger, lasts longer, resists cold temperatures and can grow in most any kind of soil, than the ones grown from cuttings.
For all these reasons, this is the way generally used in the olive regions of Europe. When the olive tree is so robust by nature and not fussy regarding the choice of soil, enjoys remarkable longevity and isn’t afraid of excessive cold temperatures.
Should the olive tree grow from the seed method, that takes about 12 years to produce or by the cutting method that takes 4 to 5 years to produce the fruit?
Grafting becomes indispensable when the tree is raised from the seed. So is cutting.
I am in favor of the seed. The plant has to remain around 7 years in the nursery. After being grafted, it still requires 3 more years, before it bears fruit. None of the methods effects the olive oil.
The reproduction of the olive tree by seed, requires time and occasionally after being seven years in the nursery, can suffer a shock from being transplanted. The roots must be dampened til the tree is safe in the ground. This is a very important task to be observed in transplanting. The trees need special care to provide us with a good quality of oil, extra virgin olive oil.
The small trees, they will develop an astonishing vigor when planted in their permanent places. Their roots will grow deep and fast, they will stand without suffering hot or cold temperatures and may be one in three hundred won’t grow.
The older trees are more delicate, because of their development in the root system.
From the late 1800s, expert Mr. W. G. Klee in a bulletin from the University of California, says that there will never be developed a root system so fine as by starting the trees from small cuttings.
He recommends to take the tops from young growing trees, when both are not too soft or too hard, having three or four sets of leaves, put them in a small frame with sand and water them a few times during the course of a month . He states that in about four months, the little cuttings will develop roots and will be ready to set out.
In the same era Mr. Frank Kimbal, of National City, San Diego County, confirms the recommendations of Mr. W. G. Klee. This is another method of producing vigorous trees, which , within four or five years, will be from 10 to twelve feet high and will start to produce olives and olive oil.
The olive is an evergreen tree and has two vegetation periods a year. One in the Spring and one in the Fall. In climates where the winters are mild, vegetation rarely stops. If the cuttings are not taken from the tree during vegetation and placed in the nursery in about a week, there is danger of more than fifty percent of them dying.
An attempt to reproduce the olive tree from cuttings which were not recently cut from the tree, and that operation was performed during a season when the sap was too active, bring poor results.
Cuttings can be made from the suckers which grow from the base of the tree. If they are taken below the grafting point of a tree, raised from a seed, the tree will have to be grafted.