Is it advisable to move our Senecio Angel Wings into a cold greenhouse during winter.

Question

At the moment the plant is in the garden border.

Answer 1

Since begonias prefer moderate temperatures, it would only be a good idea to move them to a cold greenhouse if you live in an area where there is no hard freeze in the winter. They won't withstand a freeze, but they can handle temperatures, generally, down to around fifty degrees.

Here's an article about Angel Wings that may be helpful. Enjoy your beautiful plant.
https://www.gardeningknowhow.com/ornamental/flowers/begonia/angel-wing-begonia-care.htm