Posted: 23/10/2015 at 08:06
Oleander are hardy down to about minus 5 degrees, however they don't like cold winds which can cause as much if not more damage than frost. I'd take them in to a cold greenhouse or cool conservatory over winter. They won't need watering in general, there'll be some leaf loss but they'll bounce back in spring. Good drainage is essential as well. So get then under cover.