Protect from strong or cold drying winds in autumn by wrapping the trunk and base with a protective material like Hessian or horticultural fleece. Bubble wrap will not work as the plant cannot breathe and encourages damp and mildew leading to rot. A good layer of bracken or similar breathable material like horticultural fleece over the rootstock should enable plants to withstand 10 or 15 degrees of frost. If in doubt, bring indoors overwinter.