How Wild Olives Still Grow Around the Mediterranean
The cultivated olive did not come from nowhere. Its wild ancestor, the oleaster, still grows all around the Mediterranean — a spiny, shrubby thing with tiny fruit, clinging to rocky ground. Knowing the wild olive explains how the tame one came to be, and why the two are never fully separate.
Botanists call it Olea europaea var. sylvestris — the oleaster, or wild olive. It is not a different species from the tree that fills the world’s groves; it is the same species in its untamed form, smaller and often shrubby, armed with stiff, sometimes spiny young growth and bearing little fruit with scant flesh over a large stone. It grows naturally across the whole Mediterranean basin, from Iberia to the Levant, on dry, rocky, sun-baked slopes where almost nothing else fruits. The oleaster is, in effect, what the olive was before people got to work on it — the same tree, dialled back to its wild beginnings.
Wild self, tame self
Domestication was slow and it never finished. Over thousands of years growers selected wild stock for bigger, oilier, fleshier fruit, and cloned the winners by cutting and grafting rather than seed. But the wild form kept growing right alongside the orchards, and the two still trade genes freely. Wherever a grove meets wild land you get feral olives and hybrids — abandoned trees reverting, wild seedlings creeping in, birds carrying stones into the scrub. The line between farmed and wild olive is genuinely blurred, which is one reason the olive is such a headache to trace back to a single point of origin.
Why the wild form still earns its keep
The oleaster is not just a curiosity for botanists. Its hardiness — drought tolerance, disease resistance, a will to survive on nothing — is a genetic reservoir that breeders draw on when they want tougher trees. For millennia the practical trick has been simpler still: dig up a wild or feral seedling, let it establish its stubborn root system, then graft a chosen variety onto it. Much of a classic Mediterranean grove is, underground, part wild. The tame fruit you taste is often riding on wild roots.
Reading a hillside
Once you know the difference you see it everywhere. A dense, low, aggressively spiny olive with small, sparse fruit and small leaves on a rough hillside is almost always an oleaster or a feral seedling, not an escaped orchard tree. Its olives are too small and too stony to bother picking. But that scrappy bush is the living ancestor of everything in the grove below — the wild original, still very much alive, still doing what it has done since long before anyone thought to plant it in rows.
| Botanical name | Olea europaea var. sylvestris |
|---|---|
| Common names | Oleaster, wild olive |
| Relation to crop | Same species as cultivated olive |
| Growth habit | Shrubby, dense, spiny when young |
| Fruit | Small, thin-fleshed, large stone |
| Range | Whole Mediterranean basin, on dry rocky ground |
| Practical use | Rootstock; breeding reservoir for hardiness |
What to remember
- Wild and cultivated olives are the same species, not two different trees.
- The spiny, small-fruited oleaster is the olive’s untamed form.
- Groves and wild olives keep crossing, so feral hybrids are everywhere.
- Wild seedlings are still used as rootstock under grafted varieties.
- The oleaster is a genetic reservoir for drought and disease resistance.
Wild olives: common questions
Is the wild olive a different species?
No. The oleaster is the same species, Olea europaea — usually classed as the variety sylvestris. It is the untamed form of the cultivated tree, not a separate one.
Can you eat wild olives?
Not really worth it. The fruit is small and stony with little flesh, and just as bitter as any raw olive. Its value is as rootstock and as a genetic reservoir, not as food.
Where do wild olives grow?
Right across the Mediterranean basin, on dry, rocky, sun-baked hillsides — from Spain and North Africa through Italy and Greece to the Levant.
Why are wild olives spiny?
Stiff, spiny juvenile growth is a natural defence against browsing animals. Cultivated trees show it too when they revert or are grown from seed.
Why does the wild olive matter to growers?
Its toughness and disease resistance are drawn on by breeders, and its seedlings have long been used as hardy rootstock for grafting prized varieties.
On a Mediterranean hillside, look for a dense, shrubby olive with stiff, spiny young growth and small, sparse fruit — that is likely an oleaster or a feral seedling, not an escaped orchard tree. Its olives are not worth picking. But here is the part worth knowing: much of the grove below is quietly part-wild too, because so many cultivated trees are grafted onto wild-type roots. The tame fruit rides on wild toughness — the domestication never truly finished.
Drawn from the botany and domestication history of Olea europaea (var. sylvestris).