If the soil naturally contains aluminium and is acidic (low pH) the color of the hydrangea will tend toward shades of blue and/or purple.
The choice of fertilser will also affect the colour. A fertilizer low in phosphorus and high in potassium is helpful in producing a good blue colour. Superphosphates and 'blood and bone' should be avoided when trying to produce blue flowers.
Through an elaborately clipped arch in the hedge on the western side of the lawn is a woodland pathway which leads down to Spencer's corner, through a field of red and white Horse Chestnuts (Aesculus hippocastanum and Aesculus carnea respectively) See post on Spencer's corner (to come). Through a similar arch, on the eastern side of the lawn, One enters the Chapel garden.
This lawn is designed mainly for Croquet and Gin on a hot summer's afternoon, but I think with the hedging and the statuary, will look just as beautiful on a frosty winter's morning.