Olives and Olive Oil
by SCMG Steven Hightower
Imagine these vignettes—
A guest goes wild over the pungent, fruity olive oil on the bruschetta you serve as a little pre-lunch nibbly. You humbly inform him that it comes from your own trees, locally pressed and milled.
You arrive at a dinner party, among a passel of other guests carrying flowers, or some bottle of wine or other, but you’re a standout when you present your hostess with a green-gold bottle of estate extra-virgin oil with your own label.
These, then, are some of the benefits of being a small, non-commercial olive grower. There are more and more of us around the County. Olives are known as Sonoma’s ‘other’ crop. To be sure, there are plenty of artisanal commercial producers, who want to make a living from olives and oil—but there’s an Italian saying that you plant grapes for your children; you plant olives for your grandchildren. There’s much truth in that when it comes to making money from the crop. But for the olive producer who just wants oil for home use, and for special gifts, and perhaps their own home-cured olives, the path can be much shorter.
A dozen years ago, my neighbor, Ed Stolman, and I attended an olive-growing seminar given at the Healdsburg ranch of Ridgely Evers, one of the pioneers of the fine olive oil industry in California. Ed, in his inimitable, larger-than-life way, imported 1600 trees from Italy and plunged into the for-profit artisanal oil business. After a couple-year delay, I bought 50 trees that were being taken out by Dutton Ranch in favor of grapes, and began the slow year-by-year process of obtaining a yield sufficient for home use and those hostess gifts.
So what might you expect, if you took the plunge with a few or a dozen trees? Newly planted trees, two-three years old from the nursery, will start to bear fruit as early as their third or fourth year after planting—although not in significant quantity. By our fourth year (seven-eight year old trees) we were getting enough for all of our use—we never buy oil at the store—and to reward our picking crew, and provide dinner gifts for the year. By now, our 12th year, our yield is normally is more than all those requirements, and we eagerly present olive oil gifts to acquaintances as well as friends.
So let’s suppose this sounds attractive to you. How do you start? How do you decide where to plant the trees; what varieties; how many and what spacing. And how do you know how much work you’re letting yourself in for?
Here is a summary of those factors, and at the end of the article, links to more extensive articles by Master Gardener and olive cultivation consultant Alexandra Devarenne, and Farm Advisor Paul Vossen.
There are only two key requirements: lots of sun and reasonably well-drained soil. Olives thrive in poor or rocky soil—they grow out of the rocks in the wild in Europe—but detest wet feet. Too-wet soil is the biggest cause in the County of poor crops, weak growth and flat-out failure. If all you have is clay—like my side of Sonoma Mountain—you must plant in mounds or berms. Olives have quite small root-balls, and will survive happily for many years in such small envelopes.
The olive variety or varieties you choose depends on what flavor profile you want in your
Sevillano is a great blending olive, but it’s very high pit-to-fruit ratio makes it impractical as a standalone. Picual, Coratina, Koroneiki and Hojiblanca are all varieties that are being increasingly grown.
A blend may well be your best bet. A look at this table should make it clear that olive oil, like wine, may benefit from blending to combine complimentary qualities.
Arbequina: Recognized for its aromatic ripe fruitiness, low bitterness, pungency, and stability
Coratina: Strongly green herbaceous, bitter, pungent, and stable
Frantoio: Very fruity, aromatic, herbaceous; medium bitterness and stability; strongly pungent
Hojiblanca: Fruity, aromatic, mildly pungent, low bitterness and stability
Koroneiki: Strongly fruity, herbaceous, and very stable; mild bitterness and pungency
Leccino: Medium fruitiness, and stability; low bitterness and pungency
Manzanillo: Fruity, aromatic and herbaceous; medium bitterness and stability; strongly pungent
Moraiolo: Very strongly fruity, herbaceous, and stable; medium bitterness and pungency
Picual: When harvested early produces a nicely aromatic fruity oil that has medium bitterness and very high stability.
Picholine: Very fruity and aromatic; medium fruitiness, bitterness, and pungency
Extracted from VARIETY AND MATURITY INFLUENCES ON OLIVE OIL by Paul Vossen
Our local pressing syndicate of five growers has a combination of the Italian varieties, Spanish Manzanillo and Arbequina with a bit of Picholine thrown in, and we get a fruity, aromatic, pungent oil that in our annual tastings shows up very well against expensive artisanal oils like McEvoy, Da Vero and Lunigiana.
A factor not to miss in selection is ease of picking. Smaller olives that don’t cluster much, such as Arbequina, Frantoio, and Pendolino, take much longer to pick than, say, Manzanillo or Hojiblanca, whose larger fruit tend to cluster along the branches making it easy to ‘milk’ them down into picking baskets by the dozens.
It may seem contradictory, but olives actually take quite a bit of water. Young trees benefit greatly from regular deep watering. A drip system is best, held high on the trunks, much like drip in vineyards, to provide for easy mowing and weeding. And weeding is important! According to studies done by Paul Vossen, Sonoma County Farm Advisor, weed competition within three feet of the trunk has a significant negative effect on foliar growth in young trees. As far as feeding, an application of nitrogen twice a year should be sufficient. Feeding after maturity can change to every other year—olives are alternate bearing, and to try and combat that, some growers feed in ‘off’ years, and withhold in ‘on’ years. As always, mulching will both conserve water, and discourage weed growth. Pruning is discouraged in early years, and in more mature trees, there are various methods and theories—there are articles and books available. The olive fruit fly has become an entrenched pest that must be dealt with, but there are now traps that are simply hung in the trees in June as a highly effective method of control.
Harvest and Milling
For more information refer to
Planting Olive Trees - DeVarenne by Olive consultant Alexandra DeVarenne
Paul Vossen and UCCE pieces on: