Olive (Olea europaea L.)
The olive tree is an evergreen tree that performs best in hot, dry areas of California; it does not tolerate wet winter soils. It is an attractive ornamental, produces table fruit, and oil.
Crop production is irregular under cool coastal conditions. Rooted cuttings are used without specific rootstocks. Space trees 16–20 ft. apart. Olives for canning and pickling are usually harvested in September and October in California..
Commercially, heavy crops of small fruit unsuited for canning are left on the trees until January or February and harvested for their oil. Some new varieties grown specifically for oil have recently been imported into California from the Mediterranean countries.
Calendar of Backyard Gardening Operations for Olives
Winter Dormant Season
- Spray with fixed copper to prevent peacock spot especially in wet years. For oil varieties, apply just after harvest.
Spring Bloom Season
- Prune trees during the bloom period.
- To reduce alternate bearing, remove more shoots from trees with heavy bloom and skip trees with light bloom.
- Fertilize mature trees with 2 lbs. of urea or 50 lbs. of compost.
- Begin irrigating trees so there is no water stress during bloom.
Summer Growing Season
- Control weeds with organic mulch or cultivation especially on young trees.
- Fertilize young trees with 1 oz. of urea under each drip emitter every month and irrigate in.
- Apply drip irrigation every day according to water use requirements.
Fall Harvest Season
- For table fruit, harvest when the fruit is still green, just before the straw yellow stage. For oil, harvest when the fruit has turned black on the outside, but the flesh is still green/yellow.
- Continue irrigation right up to harvest if weather is dry; do not allow fruit to shrivel.
- Apply fixed copper to prevent peacock spot before first major fall rains. Wash copper off fruit prior to processing or apply after harvest.
- Olive Fact Sheet, UC Fruit and Nut RIC
- Olive Links, UC Fruit and Nut RIC
- [PDF] 2004 Olive Fly (OLF) Update for Table Olive Industry and OLF Management FAQs
- Olive Fruit Fly Pest Note, UC IPM
- [PDF] Olive Fruit Fly Pest Note, UC IPM
- [PDF] Olive Fruit Fly, Paul Vossen, Lucia G. Varela, Alexandra Devarenne
- [PDF] The Spanish “Olipe” Trap for Organic Control of Olive Fruit Fly, Paul Vossen, UCCE Sonoma
- A Homeowner's Guide to the Olive Fruit Fly, The Olive Oil Source
- Olive, California Rare Fruit Growers
- [PDF] Olive Varieties for Planting in the Home Garden, Paul Vossen and Deborah Silver, Sonoma and Marin Co. UCCE
- [PDF] Olives: Safe Methods for Home Pickling, Sylvia Yada, Linda Harris, George York, and Reese Vaughn