Pruning shrubs is a maintenance practice required to keep the shape of the plant, prevent disease, train the plant when it is planted and growing and improving the shrub flowers fruit and stems. Although pruning can be a bit intimidating at first, especially with an overgrown shrub, once the general principles of pruning an ornamental are learned, the process becomes almost mechanical in nature.
Inspect the shape of the bush to determine the style of pruning you will use. Shrubs that come from one, main stem will require heading, or removing branches back to a healthy bud, while shrubs that grow from several places at the ground will require thinning, according to the University of Missouri Extension. Some shrubs may need both styles of cutting to remove damaged or broken limbs without damaging the rest of the plant.
Make pruning cuts above a healthy bud when heading, to promote new growth, advises the University of Missouri Extension. As your shrub grows, you will be able to determine how old a branch is by where the branch starts.
Make pruning cuts at a 45 degree angle recommends Iowa State University. Cuts that are too angular or flat will cause poor healing and reduce new growth.
Prune shrubs right after the shrub blooms, if it is a spring flowering shrub recommends the Purdue University Cooperative Extension. This allows new growth during the summer. Shrubs that bloom in the mid-summer or fall are best pruned in the winter during the dormant period.
Remove one third of all canes on a shrub in three consecutive years to reduce the size of an overgrown shrub recommends the Iowa State University Extension. Head prune the branches as they grow to direct them.
Train new evergreen shrubs by removing a third of new growth in the first two years, before allowing the shrub to grow on in the third says Iowa State University.