Answer: Allow the plants to settle in and begin growing before you prune them. Once they seem to be growing well, a rule of thumb would be to shear the tips and sides every time they grow about six inches while they are small. As they get larger, increase that a bit until you are trimming to maintain the size you have in mind. This early trimming will encourage heavy branching from close to the base. (Each time you cut, you stimulate branching. You will be able to see how this works by observing how the first trimming affects subsequent growth.) Be sure to maintain a slight slope to the sides so that the base is wider than the top. This will allow light to reach the lower branches and help keep them full. It may seem difficult to cut such small plants, but in the end you will be glad you did. If, after a few years, you think the hedge is not dense enough, you can cut it off quite short and allow it to regrow, being sure this time to trim often enough. During the first year and after any severe pruning be sure the plants receive adequate water and nutrients to achieve a vigorous growth level.
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