Summarize this article in one sentence.
Spring and summer are the growing seasons for Leyland cypress plants. You can trim the plant throughout this period, but you are better off saving heavy pruning for the beginning of spring. Cutting the plant after August leaves it exposed to harsh winter weather, which can kill your cypress. Brown needles are a sign of winter damage. If new growth doesn't replace the needles, you will need to prune the branch below the brown coloring. Cypress plants need regular buzzes to keep them within their yard boundaries. Using clippers, cut the ends of all the long branches. Make them even so your cypress looks neat and pleasant. Plan on doing this several times throughout the spring and summer. For example, you might trim the cypress in April, July, and then August. Leyland cypress has a tremendous growth rate. If you do not trim it regularly, it can get large and hard to control. The ideal shape for a Leyland cypress is an A. That may seem odd, but the wider base prevents the plant's bottom from rotting. You can shape the cypress while you trim it annually with clippers and while you prune long branches with shears. If you grow the cypress as a hedge, you can trim its top flat. A Leyland cypress will grow this way naturally. You only have to perform regular trimming to prevent the plant from overgrowing if you have a limited amount of yard space. Always look for weak branches. They may appear dark brown, black, or splintered. These branches may simply be damaged, or they may be a sign of disease. Using a sharp pair of loppers or shears, cut the branch below the damaged portion. You can prune damaged branches throughout the entire year, so take care of them as soon as you notice them to prevent problems from spreading.

Summary:
Perform routine trimming in April through August. Trim the top and sides 2 to 3 times during the growing season. Shape cypress hedges into an inverted wedge so light reaches its base. Remove damaged branches as you notice them.