The best time to trim bushes is during late winters or early spring that is from March to early April. Heavy trimming in late winter or early spring can eliminate the flower display for 2 or 3 years. However, the appropriate amount of trim can restore the health of shrubs. But make sure not to overcut the bushes as it can take time to grow and need more maintenance. However, when you trim shrubs, make sure to remove its dead stems as soon as you see them. Because dead stems can attract insects and cause diseases. Also, take out crossing branches and water sprouts.