Olive trees are only hardy in milder areas and in sheltered sunny positions, ideally south or west facing with some protection from the north and east winds. They don't tolerate temperatures much below -5 degrees for any length of time, so I would want to know which area you are in before suggesting that you plant them out. If you do feel that you can provide these conditions, then I'd suggest that you plant them while they're dormant, preferably in the early spring in case of another hard winter, as the roots need time to get established in their new home.

Plant in free-draining soil that will not become waterlogged during the wetter parts of the year; they tolerate both acidic and alkaline soils. Poor sandy soils will need added organic material, and clay soils may require additional drainage or if this is not feasible, then consider a raised bed.

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