Harvesting Olives
One of the most exciting aspects of growing olive trees in the UK is the possibility of harvesting your own home-grown olives. While our climate presents more challenges than the Mediterranean, many gardeners successfully produce fruit with the right conditions and expectations. Understanding when and why olive trees fruit, what factors influence production, and how to harvest and cure your olives will help you maximize your chances of success. This section addresses the realities of fruiting in British conditions, managing your expectations while providing practical guidance on encouraging fruit production, recognizing when olives are ready to pick, and transforming bitter fresh olives into delicious table olives for your kitchen.
Will my olive tree produce fruit in the UK?
Yes, olive trees can fruit in the UK, particularly in southern, coastal, and urban areas with milder microclimates. Fruiting requires a warm summer (for flowering), a cold winter period (vernalisation), and mature trees (3-5 years old minimum). However, crops are less reliable and abundant than in Mediterranean climates. Many UK growers enjoy occasional small harvests.
When do olive trees flower and fruit?
Olive trees flower in late spring (May-June) with small creamy-white blooms. Fruit develops through summer, typically ripening from October to December depending on variety and weather. Green olives are picked earlier; black (fully ripe) olives are harvested later. In the UK, full ripening may extend into winter in cooler years.
How long until my tree produces olives?
Container-grown olive trees typically begin fruiting at 3-5 years old, though this varies by variety, growing conditions, and tree care. Some precocious varieties may flower younger. Patience is key; once fruiting begins, trees can produce for decades. Grafted trees fruit sooner than seed-grown trees.
Why isn’t my olive tree producing fruit?
Common reasons include insufficient age (under 3 years), inadequate winter chill (olives need a cold period), lack of sunlight, over-pruning of flowering wood, or unfavourable weather during spring flowering. Excessive nitrogen fertiliser promotes leaves over flowers. Some years are simply better than others; olive trees naturally have “on” and “off” years.
How do I harvest olives from my tree?
For small harvests, hand-pick olives or gently strip branches, catching fruit on sheets below. Harvest green olives when they reach full size but are still firm. Black olives are fully ripe but harvest before they become wrinkled. Wearing gloves prevents hand staining. Commercial growers use rakes or mechanical shakers, but hand-picking prevents bruising.
Can I eat olives straight from the tree?
No, fresh olives are extremely bitter due to oleuropein, a compound that must be removed through curing. Raw olives are inedible and unpalatable. All olives require processing, whether through brine-curing, water-curing, dry-salt curing, or lye treatment before they’re suitable for eating. This process takes several weeks to months.
How do I cure olives at home?
The simplest method is brine-curing: make small slits in each olive, submerge in 10% salt solution (100g salt per litre water), change water weekly for 4-6 weeks until bitterness disappears. Taste-test periodically. Store cured olives in fresh brine with herbs, garlic, and lemon in the refrigerator. Water-curing (daily water changes) is gentler but takes longer.
What quantity of olives can I expect from my tree?
In the UK, yields vary dramatically. A mature tree (10+ years) might produce 5-20kg in a good year, but many years may yield little or nothing. Trees alternate between heavy and light cropping years naturally. Mediterranean trees can produce 50kg+, but UK conditions are less favourable. Grow olives primarily for ornamental value with fruit as a bonus.
Do olive trees drop fruit and make a mess?
Yes, unpicked olives will eventually drop, potentially staining patios and paths. If you don’t want the fruit, remove flower buds in spring or pick green olives early before ripening and dropping. Alternatively, position trees over grass or borders where fallen fruit isn’t problematic. Some gardeners actually prefer the minimal fruit mess compared to many other fruit trees.
Can I make olive oil from my UK-grown olives?
Technically yes, but practically challenging. You need substantial quantities (roughly 5-6kg of olives per litre of oil) and access to pressing equipment. Home pressing is difficult without proper machinery. Most UK growers with multiple trees either cure olives for eating or take large harvests to community pressing facilities. Small harvests are better suited to table olives.