Hedges provide gardens with frames and focal points | In Fiona's Garden

We were there one May when the sun was already hot, and our visit coincided with the annual box clip.

The gardeners were happy to ease their aching backs for a few minutes' chat and told us that if clipped in May, the box and yew needed pruning only once a year.

I used to worry that our summer sun would burn a just-clipped hedge's new growth, but so far, this it hasn't happened.

Wet weather delayed the prune this year, but finally, it's done, and the garden's appearance has been transformed.

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It's amazing how a neatly clipped hedge pulls overflowing shrub and flower borders together, anchoring the design and providing frames and focal points.

I have far too many hedges, but each does a good job and brings its own special character to its corner of the garden.

My box (Buxus) hedges are all grown from cuttings from two plants originally from Bill's mother.

European box (B. sempervirens) is probably the most common hedging box, with small, oval, dark green leaves, slow growing, happy in any soil and virtually impervious to drought and frost.

It frames two squares of lawn in our back garden and edges a brick path to the washing line.

I also have a couple of variegated leaf forms, cream and yellow, excellent as topiary for lighting up shade.

The bright, shiny green leaves of Japanese box (B. microphylla) are rounder and, despite its botanical name, slightly bigger.

It's great for clipping into cubes, cones and balls to frame an arch or close a long vista.

When choosing hedging plants, you need to balance speed of growth against frequency of clipping.

Box is slow growing and thus labour saving but if you fancy something fast and don't mind the extra clipping, try one of the many forms of pittosporum, some dwarf(ish) and some that are streaked and splashed in shades of cream, white and gold.

Our two grandsons helped me plant a hedge of Pittosporum 'Golf Ball' around a fountain 18 month ago.

It has grown rapidly into a hedge and just had its first clip. It looks terrific, but time will tell how dwarf it really is.

Laurustinus (Viburnum tinus) makes a tall, tough hedge with oval, matt green leaves and pink and white flowers in winter. Mine survived a fearful attack of thrips last year and was stripped almost bare but recovered and is now as dense as before. It survives on an annual November trim.

Bay (Laurus nobilis) has hauntingly fragrant leaves and is a good alternative, slow growing and excellent in shade.

For a silver and grey garden, wall germander (Teucrium fruticans) makes a brilliant hedge in no time flat. I let it flower in November before trimming; it brings so many bees to the garden.