In cold climates, most tender plants and not very hardy ones will need protection from frost and wind in order to survive the cold season. It is best to select the plants that you are growing to grow in your garden so that they will thrive in your climate. If you are planning to grow very tender plants in a cold climate will end in disappointment as they will not survive the hard conditions of the cold winters. They will need to be grown under cover in order to survive. For some of the not very hardy plants that normally do well in a site but may suffer in harsh winters, providing protection against wind and frost over the cold period is a necessary precaution for them to survive.
The best protection is given by preventive measures. To avoid the worst effects of frost do not plant in frost pockets. Choose sheltered sites, such as in front of a warm wall or a sunny bank, for susceptible plants. Place tender climbers against a house wall instead against a garden wall, as the first one will be warmer, or better grow them in containers that can be easily moved to a sheltered place when needed. Other tender plants, like seedlings, summer bulbs and tubers, should only be planted out when all danger of spring frost has passed. Another preventive measure is to not feed roses and other shrubs late in the season since this encourages new, soft growth that may be damaged by autumn frost. Allow herbaceous perennials to die down naturally. This way the foliage and stems will protect the crowns in winter. Provide a deep mulch of slowly decomposing organic matter to offer protection to the roots of all plants. Check plants regularly over the winter and firm any that have been lifted out of the ground by frost.
Frost protection means to insulate the plants from extremes of freeze and thaw conditions by maintaining a constant temperature. To protect the top growth from damage, wrap the plants in hessian, carpet or double thicknesses of newspaper. For plants that need extra protection, place bracken or straw packed around the plants beneath the hessian. When temperatures rise above freezing the cover can be removed. Small shrubs and trees that are grown in areas with temperatures below their usual hardiness level can be protected by building a loose wire-netting cage around them and then packing this with dry leaves or straw. To keep the insulating layer dry, place plastic sheeting tied or stapled over the top of the cage. Alternatively pack the straw in between and behind the stems before covering over. Perennials that die down to a resting crown can be protected by placing a mulch or a few forkfuls of leaves over the crown and keep it in place with bracken or prunnings from evergreens. Roses and other woody plants can be protected by mounding earth around their base or laying them in a trench. In very cold areas cover the earth mound with a layer of straw. Protect root vegetables in the same way and then they can be harvested even during frosty spells. For few individual plants the best solution to protect them is to use a cloche. For emerging shoots of frost-sensitive plants the easiest way to protect them is to place a container or a tough cardboard box over them. For more permanent protection you can use glass cloches, polythene panels, polytunnels or cold frames.
Wind protection, if made efficiently, will allow you to grow a wide range of plants. This is particularly useful for large plants, for plants grown in open ground that cannot be easily brought under cover and for early-flowering plants and trees that are more susceptible to frost than later-flowering species. Protection is also needed from strong winds, as they can cause broken stems and browning of foliage. Wind protection aims to reduce the wind speed before it reaches the plants. This way is reduced the physical damage to branches and stems and is prevented further water loss. Tender plants will survive better is planted in the lee of a good hedge. A 1.5 m tall hedge will reduce the wind speed by 50% for plants within 7.5 m of the hedge. There are tree and shrub species that are more tolerant to wind than others. The most tolerant are those with small, thick, spiny or waxy leaves. Windbreaks made from canes and netting or proprietary products will aid a hedge while it is becoming established.