This harsh Winter has really put a lot of borderline hardy plants to the test. We recently planted 3 massive Olive trees at the Institute for Manufacturing at Cambridge University which was opened by HRH The Duke of Edinburgh.
Although we have been led to believe maximum continual tolerance for Olive trees was 12 degrees below – the very heavy frost at 17 degrees seems to have been tolerable for these particular plants as they look fine!
‘The area where these particular Olives are is a courtyard surrounded on three sides by high buildings. This creates a micro climate and shelter for the Olives so they have probably fared better than other Olives in more exposed areas.
Most Olive trees in this country are grown in containers and that is where most of the risk lies. Water can end up freezing within the container so to stop this happening it is worthwhile to cover the outside of your Olive containers with fleece to keep them warm throughout the Winter. And then when risk of frost is gone (May) take it off.’