The first step is to get rid of the rubbish and dig out tired old shrubs and weeds, especially perennial weeds such as thistle, nettle, bindweed, ground elder and couch grass. Remove all parts of the roots: rhizome, tap root and bits of brick bat. But, don’t be over hasty. Keep an eye out for surviving plants. This is especially important in winter when they may be ‘resting’ below ground. Let them grow, and if they’re no good take them out. But remember, they may turn out to be a real treasure.