One of the classic blue shrubs (in more acid soils) is the Hydrangea macrophylla, or common hydrangea. This has become almost a signature plant of gardens in the U.K. and it's easy to see why, because it provides endless Summer Hydrangea. Hardy and requiring little maintenance, it delivers year after year, over a long flowering period from midsummer to late autumn. Hydrangea macrophylla is in fact divided into two categories. The most frequently encountered are the 'mopheads' or 'Hortensias'. These are the ones producing big, confident, dome-shaped blooms. 'Blue Bonnet' or 'Goliath' are examples.

If you are looking for something more unusual, the 'Lacecap' hydrangeas provide an exciting alternative. The flowers of the lacecap hydrangeas are quite different from those of the mopheads. They are made up of two parts - an outer ring of showy florets and a central arrangement of small fertile flowers. Hydrangea 'Blaumeise' is a wonderful lacecap to look out for. Also known as 'Blue tit' or 'Blue sky' it produces exceptionally deep blue coloured flowers set against dark green leaves.

Another great choice if you're looking for blue flowering shrubs is the buddleia. Ideal in a border, the arching stems, tipped with clusters of flowers of varying shapes and colours (depending on species and variety) are, like the hydrangea, a classic sight in the summer garden. 'Black Knight' and 'Empire Blue' are examples of Buddleia davidii bearing flowers with blue and purple hues whicb are very attractive to butterflies. 'Lochinch' and 'West Hill' are other examples of bluish buddleia.

Lavender is a shade in its own right, and fields of the plant shimmering under a hot sun are an image to take home from Mediterranean holidays. Bring some of that romance into your garden with one of the hardy lavenders grown in this country. Lavenders will bring fragrance and colour to shrub borders or rock gardens. They can also be used to form a low hedge, perhaps around a vegetable area.

Three very different shrubs, all with the potential to bring the beauty of blue into the garden. As with many shrubs, none of these require much maintenance and will thrive in most garden soils (though for best blues from your hydrangeas your soil needs to tend towards acid). Blue can be bold or it can be demure. Either way it is always the height of good taste.