Frost protection is one of the easiest to solve, cover the plants or trees with something like old net curtains ie it is light will allow rain through together with sunshine, even if it is only a small amount. You could also buy the equivalent of fruit cages (which normally are made of a mesh to keep birds etc, out, that can be covered in a similar material, alternatively make an upturned "U" shaped frame of a light type of wire and cover in this case you could use a polythene to cover, but leaves the ends open so as to leave ventilation and the plants do not burn (it can happen even with weak sunshine. On the other hand if you are thinking of plants in pots, use hessian, sacking or any form of insulation around the pots to stop frost getting at the roots, and add a good layer of mulch or peat at the top of the pots. These and many more tips may help you on my site www.gardeningforyou.com

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