Most can be cut almost to the ground if they are too large. Otherwise, thin the branches by cutting some at the base, or cut back those that are reaching too far. Watch for red spider mites on evergreens as the weather gets warmer. They make tiny webs inside the plant that catch dirt and debris. The spider mites suck the sap out of the plant as their source of food and can seriously damage young trees if they are not controlled.
Control is simple.
Because they prefer dry, dusty places spray the evergreens with water. Use as strong of a stream of water as the tree can withstand, and do it every day as long as the weather is hot and dry. Iron chlorosis can be a problem on trees and should be treated as soon as it becomes evident. If the leaves are yellow with green veins, they are lacking iron. Either spray the leaves with a foliar iron application, or make holes around the drip line and fill them with a mixture made of about 5 gallons compost, one cup ammonium nitrate and 2-3 tablespoons horticultural sulfur.