When to Harvest Olives and How to Cure Them at Home

Olives can be picked at any stage from green to black; the colour you pick at decides how you use them. In the Northern Hemisphere green olives are harvested in September–October and black olives from November to January; in the Southern Hemisphere roughly March to July. Whatever the colour, raw olives are extremely bitter and must be cured before eating.

Green, Purple or Black?

• Green: full size but still firm and green. Best for crisp, Spanish-style table olives.
• Turning (purple-pink): the classic stage for high-quality, fruity olive oil and for Kalamata-type olives.
• Black (fully ripe): soft, dark through the flesh, more oil but milder flavour. Good for dry-salted olives.

Test ripeness by squeezing: a ripe olive gives a little and its juice turns from clear to milky to purple as it matures.

How to Harvest

• Hand picking: best for table olives; avoids bruising.
• Raking or combing: plastic rakes pull olives onto nets spread under the tree.
• Shaking: handheld or tractor-mounted shakers for oil olives; super-high-density hedgerows use over-row harvesters.

For oil, take the olives to the mill within 24 hours; olives left in heaps heat up and ferment.

Why Olives Need Curing

Fresh olives contain oleuropein, a very bitter compound. Curing leaches or breaks it down. Commercial producers use lye (sodium hydroxide) for speed; at home, water, brine and salt are simpler and safer.

Method 1: Water Curing (green or purple olives)

1. Slit each olive once with a knife or crack it lightly.
2. Cover with cold water in a jar or bucket; keep them submerged with a plate.
3. Change the water every day.
4. Taste after 1–2 weeks; most olives need 2–4 weeks until only slightly bitter.
5. Finish in brine (see below) with herbs, garlic or lemon.

Method 2: Brine Curing (green, purple or black)

1. Make a brine of about 100 g salt per litre of water (10%).
2. Pack olives (slit or whole) into clean jars and cover with brine, a little vinegar on top is optional.
3. Seal loosely and keep cool and dark for 2–6 months, changing the brine once a month.
4. Taste; when pleasant, store in a fresh, weaker brine (about 6–8%) in the fridge or pantry.

Method 3: Dry Salt Curing (ripe black olives)

Mix ripe black olives with coarse salt (about one part salt to two parts olives by weight) in a basket or mesh bag, stir every day and let the juice drain away. After 4–6 weeks they are wrinkled and ready; rinse, dry, toss in olive oil and store in the fridge.

More Olive Tree Guides

• How to Grow Olive Trees: The Complete Guide
• How to make olive oil at home
• Olive tree yield and years to fruit
• Is olive farming profitable?

Frequently Asked Questions

Can you eat olives straight from the tree?

Technically yes, but they are so bitter that almost nobody can; they need curing.

Are green and black olives from different trees?

No. Black olives are simply riper versions of green ones from the same tree.

How long does it take to cure olives at home?

Water curing about 2–4 weeks; brining 2–6 months; dry salting 4–6 weeks.

When is olive harvest season?

September to January in the Northern Hemisphere and about March to July in the Southern Hemisphere, depending on variety and use.