We all love butterflies and hedgehogs in our gardens. These welcome visitors need food, shelter and somewhere to breed and we need to provide for all their needs if we expect 
them to come and to stay. If we want to encourage wildlife to visit our gardens we need to plan which plants we use in our borders, which trees to grow and which weeds to allow.
We need to provide pollen and nectar-rich flowers for as much of the year as possible for insects. We need to provide insects, seeds and berries to encourage a wide variety of birds to our green gardens.
Design Principles for a Wildlife Garden
Variety
Variety is the keyword. The more different environments we can provide the wider the variety of insects, birds and mammals we will find in our wildlife-friendly gardens.
Every different plant is its own micro-environment. If we cut half of the lawn every week and half every two weeks those will be different environments and will suit different insects.
Insect friendly environments include clover and nettles. Allow a few nettles to thrive behind your shed or in a dark corner somewhere. Sow clover as green manure between crops in the summer and encourage insects at the same time.
A compost heap encourages all manner of invertebrates and is essential for maintaining a healthy soil.
If you grow a hedge, think carefully about planting a mixed hedge because that will encourage more species of insects and birds than a single species monoculture hedge will.
Insects
Take care of the insects and the birds will take care of themselves. At least some birds will. When birds have nestlings to feed they need to visit their nest every few minutes with a beak full of wriggly things. If you have a large variety and number of insects in your garden in spring you are more likely to have birds nest in it.
Some insect species like lacewings, ladybirds and hoverflies prey on less desirable insects like aphids. You can encourage these garden-friendly insects by planting open flowers of the daisy family and shrubs with open flowers like hypericum and apple trees. If you plant enough hypericum and chrysanthemums you will be hard put to find any greenfly.
Willow provides pollen and nectar as early as February and are superb for bumble bees that forage earlier than honey bees. Besides which the catkins look stupendous.
Seeds
Some birds feed mainly on seeds so let seed heads form on perennials and leave them on the plant rather than being too obsessively tidy. Grow shrubs and trees that have berries as well as flowers. Crab apple, hawthorn, amelanchier and honeysuckle all provide wonderful food supplies for birds from summer until spring.
Shelter
Hedgehogs are the main mammals that gardeners try to encourage because each one eats around 150 slugs every night. That means you can do without copper slug bands and definitely without slug pellets.
Hedgehogs need shelter in the daytime, which they usually find in the leaf litter at the bottom of a hedge. (Another reason to plant hedges instead of fences). They also need somewhere to hibernate. You can encourage them to hibernate in your garden by leaving piles of woodchips and twigs in odd corners, as well as piling up leaves to rot down in compost bins.
The same hedges and shrubs will provide nesting sites for birds in spring. Compare all these benefits of hedging shrubs to a waney lap panel fence and it makes you cry every time you see a new fence going up.
