Winter Protection The answer really lies in preparation. It is at about this time of year that plants in their pots are moved back into the greenhouse or cold frames, try placing ground level pots on plinths of polystyrene to protect from the cold coming through the ground. Our plants left outside in pots are placed on black plastic bags filled with insulating material such as polystyrene or crushed or shredded paper (black retains the days heat) with a bubble wrap surround. One of the best products to really become available recently is the poly-fleece. One way we have found to protect our tender perrenials is to build a bamboo wigwam, and dig a trench around the outside of the root ball or pot. Wrap the fleece around the wigwam and back fill the trench to keep the bottom of the fleece in place. Ensure that there are NO gaps, as even the slightest hole will destroy the macro climate inside. When placing plant pots for winter protection remember that cold air drops. This means that you should allow air to fall away from the pots. Again if there is no choice about the sighting of the pot we pop it on top of some polystyrene to raise it above the cold air flow. Remember it is the frost into the roots that will certainly kill a plant, and wet pot compost will allow the water to freeze, and damage the roots, hence the importance of keeping plants dry or just moist and protecting the ground from the frost. Plants I am concerned about in the garden get a thick helping of mulch from the composter. I also keep a bin full of chopped down woody waste, this is applied over the top and for me seems to work very well. It is all really quite simple, think of yourself planted up to your knees in soil, no clothes on, battered by all that can be thrown at you. Then think ‘what would I do to protect myself’. You put on a coat, keep the ground around your feet dry to prevent frostbite or trenchfoot. Leaning on a support for the winter so that the winds don’t batter you, and try to get us much sunlight and warmth as possible.
Looking at the weather patterns around most parts of the country it is not easy to say that one rule applies here and another there for protecting plants through the winter, but one thing is clear, the nearer the coast you are the less extreme the weather can be. It seems that at the moment it is getting more and more difficult to predict the likely winter events. However, we have found various means of protecting our plants, usually with a great deal of success.