Olive trees originated in the Mediterranean and, according to the Texas A&M University, can be traced back to biblical times. Some olive tree varieties will long outlive the planter, meaning special consideration needs to be made before planting, ensuring the tree is in the correct growing conditions to survive.
Olive trees do well in warm, Mediterranean conditions. Tree growth begins after the average temperature outside is around 70 degrees F during the day. Olive trees set fruit buds during the winter, which then produce the fruit during the warmer months. Winter temperatures below 17 degrees F will damage the tree, and it may die if the soil temperature drops below 10 degrees F.
Olive transplants, says the University of California Davis, often come in 4-inch pots, or 1-gallon containers. The 4-inch potted plants usually range between 18 and 24 inches in height, while the 1-gallon sized plants are between 4 and 5 feet tall, with branches starting at 3 feet. For transplanting purposes, trees should be actively growing when you buy them so that they continue to grow when transplanted. Planting during the dormant period will often cause stunted growth.
Spacing and Soil
When planting multiple olive trees, space them at least 20 feet apart to give roots ample room to grow. Most dwarf and compact olive tree roots will still reach around 20 feet. Olive trees prefer a soil with a pH of 5.5 to 8.5. Olive trees will adapt to a wide variety of soils and soil conditions. Soil must be well draining, as olive trees have a shallow root system that does not adapt well to flooded areas.
Olive trees require a hole dug to the size of the container when being transplanted. It is important that the roots are checked upon removal of the container; any damaged or diseased roots are pruned away. Soil form the area is required when burying the root ball. Potted growing medium should be avoided to prevent poor root growth.
Olive trees should not be staked because the trunk grows stronger without them. When trees topple over, the top of the plant should be trimmed away, or it should be tied lightly to a stake, but only until the tree can stand on its own. Trees in windy areas may require staking. Remove all weeds from around the base of the olive. After transplanting, olive trees require daily irrigation to stay healthy during the summer. Irrigation tubes may be used at the base of the plant in the first year, then moved 24 inches away from the trunk in the second year to prevent disease and over watering.