How hardy is an Olive Tree? The simple answer to this is “Very Hardy”.
Mature Olive trees will happily survive with no ill effects whatsoever in temperatures as low as -15 Celsius. Younger Olive trees can survive in Temperatures down to -12 Celsius without the need to cover them with fleece.
The Olive tree is a fruit tree so requires at least two months of cold weather to flower and fruit. Duration of cold weather is something to consider. If the temperatures drop early evening and continue to do so well into late morning the next day for long periods then you may well need to wrap your tree in fleece.
Temperatures lower than this can cause scarring to the bark but this will heal and contributes to the gnarly effect that we all know and love.
For the gardening enthusiast, it is possible to have olive trees almost anywhere. London’s Kew Botanical Garden has an olive tree that still yields fruit. Given the right conditions an Olive tree will produce fruit even in England.
The most important thing is to make sure the ground around your Olive isn’t too wet in the winter.