Freezing weather - with or without snow - can delay both delivery and planting. The key point is this: Roots break easily if they are moved while frozen. Most of a plant's energy is stored in the roots during winter. Broken roots lead to poor growth in spring and the plant will simply die if the damage is bad. The roots don't actually have to snap off: they will die below the point where they were bent while frozen. You cannot do any planting when your soil is frozen or when air temperatures are below zero. You should store your plants in a cold place (outside is best) but never in direct sunlight. 

Open the parcel so the tops of the plants are in the open air. You will find the roots are in a black polythene bag and they should stay inside this while the freeze continues. You should not store your plants indoors although a cold outbuilding is fine. You must not move your plants at all during freezing weather after you have stored them. 

When can I get planting? When you can dig the ground comfortably, unpack the plants on a day when the temperature is above freezing, wet their roots really well and plant them as normal. You can watch our How to Plant videos for more help with this bit.