Oleanders aren’t naturally hardy, which means they really can’t handle freezing temperatures on their own. The best way to keep them safe from the frost is to move them into a proper winter shelter. However, if you live in a milder climate, there are a few ways you can help your oleander survive the winter outdoors.
Oleanders Aren’t Winter-Hardy
Since oleanders hail from the warm Mediterranean, they aren’t built for the cold. They can usually handle a quick dip down to about 23°F (-5°C), but they’ll quickly show signs of serious frost damage if it stays that cold for long. Since our winters often get much chillier than that, knowing how to properly overwinter your oleander is key to keeping it healthy.
The Best Way to Overwinter Indoors
My rule of thumb is to leave your oleander outside as long as possible and bring it back out as early as you can in the spring. When it is time to move it inside, look for a spot that is bright and cool, but definitely frost-free. Trying to overwinter an oleander in your living room usually doesn’t work out well because it’s just too warm. Instead, opt for a dry basement, a garage with a window, or a sunroom. You want to keep the temperature below 50°F (10°C); if it gets warmer than that, the plant won’t go dormant and will try to keep growing, which weakens it in the long run.
Keeping Your Oleander Outdoors
If you’re expecting a mild winter without much snow or hard freezes, you can try overwintering your oleander outside. Just make sure you give the whole plant plenty of extra protection.
Move your potted oleander to a sheltered spot—ideally right up against a house wall or under a roof overhang. To keep the roots from freezing, place the pot on an insulating base like a wooden pallet or a thick piece of Styrofoam. Finally, wrap both the plant and the pot in bubble wrap or a heavy-duty garden fleece from your local nursery.
Some Varieties Handle the Cold Better Than Others
Just like they vary in flower color, different oleander varieties have different tolerance levels for the cold. If you live in a slightly cooler zone, you might want to look for these varieties, which are known to be a bit tougher:
- Villa Romaina
- Album Plenum
- Papa Gambetta
- Italia
- Lutein Plenum
But a word of caution: even these “tougher” types aren’t fully winter-hardy. They still need a cozy winter home or some serious frost protection to make it through to spring!
