This dwarf form of box makes a perfect 12-15" hedge.  It has very small leaves and has a nice compact habit which makes it perfect for knot gardens and parterres. Its leaves are dark green.  Once established and at your required height (it will grow to 2.5-3ft if you want it to), it will need clipping twice a year (three times if you want perfection).  Box likes a well-drained soil, so a waterlogged site is not a suitable site for box (or yew) hedging.  Plants when supplied will vary between 15cm (6") and 25cm (10") depending on the time of year supplied.  Spacing for dwarf box is 3-4" but once at this size you will not manage to get them closer than 5-6" which is the approximate size of their rootball diameter.  
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