As any gardener knows, winter is not always kind to plants. Wind, rain and particularly frost can all cause damage but, with a little forethought and planning, it is possible to ensure your plants make it through the winter in excellent shape.
The type of protection required will depend on the plants concerned. However, several basic rules can be applied to most gardens.
As autumn advances, it is prudent to avoid feeding plants with fertilisers rich in nitrogen. This type of fertiliser encourages soft, sappy new growth that is particularly vulnerable to frost.
Applying a thick layer of mulch to borders and beds is an excellent first line of defence, providing warmth and insulation to plants. You can also use slate chips, bark or gravel. The plants themselves should be surrounded by grit in order to keep out excessive moisture and help keep the roots safe from rotting.
Plant in the right places
Ensuring that new plants are placed in the most appropriate spots for their needs can help ensure that they survive and thrive. For example, plants, such as camellias, which flower early in the year, should be sited so as to ensure they do not get the first morning sun. This will protect their delicate buds from thawing too rapidly, in a process that can damage or destroy them.
Locate containers carefully
Containers and pot plants left outside for the winter should be placed in order to give them maximum protection from the weather. This may mean grouping them closely together in a sheltered area. You can also use bubble wrap or straw to insulate a pot and prevent the roots inside from freezing. Sinking a pot into the soil until only the rim is visible, also works well as a frost-protection measure.
With the appropriate protection, it may be possible for tropical species, such as banana or lemon plants, to survive the winter outside. You should remove the leaves until only the bare trunk or stem remains, then surround the trunk or stem with wooden stakes. The stakes will help shield the plant from the wind and also provide space for an insulating layer of straw. Wrap the whole lot with willow fencing, secure with gardener’s twine and, finally, stuff any gaps with more straw.
Some plants, even if mulched, well wrapped up and sensibly located, will not survive winter in a British garden. Succulent plants are one example; these need to overwinter in a well-ventilated greenhouse if they are to avoid destruction by frost. Good ventilation is particularly important: without that, they will suffer excessive moisture. As well as particularly vulnerable species, a wider variety of plants may need the protection of a greenhouse in more exposed gardens. Typically, rural sites tend to be more vulnerable to frost than city gardens because they do not benefit from the heat retained by large numbers of surrounding buildings. Although it may not be practical to move everything that is susceptible to frost damage, it should be possible to take cuttings of favourite plants and overwinter them in a greenhouse.