Get the best out of your outside space by calling on your garden 'friends'. Introducing helpful wildlife into your garden will help to control pests, maintain a natural chemical-free balance and encourage your garden to bloom, whether you have a large garden, an allotment or a simple window box. Some plants are great 'friends' and are endlessly useful - sweetpeas are good for regenerating tired soil, for example, while marigolds repel pesky greenfly...