Prevention is far better than cure, so try to minimise the damaging effects of cold on your plants:
Cold air and frost always descend to the lowest point in a garden so avoid planting tender plants in obvious frost pockets.
The ever-increasing number of tender plants on offer may not withstand sustained cold without some form of protection. How you protect your plants from the effects of cold depends on the type of plants and the situation they are growing in.
Damaged plants
If your plants do get frosted this doesn't necessarily mean the end for them, many plants will recover given time. However there are ways of minimising the damage:
Dealing with snow
The benefit of snow is that it acts as an insulator, protecting plants from the cold and frost, however, a heavy layer of snow can also cause leaves and branches to break, so it's important to know how to deal with it when it arrives: