For a dense wall of privet, plant a single row of shrubs with about 16 inches of space in between each plant. Dig a hole that is deep enough for the entire root ball and at least 1 1/2 as wide as the root ball. This loosens the soil around the shrub so it can begin to put out roots and improves soil drainage around the plant. Privets aren't particular about soil type, but prefer a neutral pH. Amend the soil with compost as you fill in the holes. Planting is best done during the spring.
After planting, water privets well. Until they begin to put on new growth, water them twice a week. New growth signals the roots have taken hold and the plants are doing well. At this point you can taper off watering, then water only when the top few inches of soil are dry. To encourage the plants to bush out, trim about a third of the height of the shrubs at this time.
Privets can tolerate heavy pruning. Pruning is best done after flowering. However, because pruning removes many of the flowering branches, you may not notice the flowers. Instead, schedule pruning for early summer. Use hedge clippers to clip the hedges into straight lines both vertically and horizontally. To reduce stress, water your hedge after pruning.
Although many people think of privets as tall walls of green, there are other options. Chinese privet only grows to about 5 feet and some varieties have green and gold variegated leaves. Golden privet has golden yellow leaves and reaches 6 to 12 feet in height. The Amur privet is a deciduous shrub. For privet leaves with a mottled grey-green center and showy white edge, look for the "Silver Star" cultivar.