Overwintering rose stems


When can I put my rose stems - which are currently overwintering in an unheated bike shed - back in the garden? And when should I prune them?

The answer

The same basic overwintering rule applies to your rose stems as it does to all pot plants: In as late as possible, back out as early as possible. Once the potted roses can generally tolerate light frost just under zero degrees, the stems can stay outside until temperatures drop to between around -2 and -5°C. That's assuming the pot is frost-proof as well! To ensure that your roses won't experience frost in the unheated bike shed, during long, cold winters, consider using small greenhouse heaters to keep the roses around the zero-degree threshold (around -2 to +5°C).

If there is no more risk of heavy frost, the roses can go back outside at the beginning of March. Early/mid-March is also the right time to give your rose stems their winter prune. If night frosts are likely later in April/May, bring them in quickly overnight.