Both pruning and thinning are intended to reduce the size of a shrub but they’re done quite differently and with different tools.
Trimming
A sheared azalea with nothing but deadwood in the interior.
This is what many people do when they’re not sure how to prune their shrubs. They get out the hedge trimmer and shear away the outermost branch tips to form a neat and tidy geometric shape (think meatballs or SpongeBob SquarePants).
For some applications, such as a formal boxwood hedge or topiary, this can be entirely appropriate.
But for most shrubs, this type of treatment results in a thin layer of green leaves on the outside of the shrub and nothing but dead stems in the interior. If a part of the shrub is damaged, there’s nothing alive that can grow in to fill the damaged area. And with few leaves available to produce “food” for the plant, it often declines over the years.
Pruning
Pruning is always done by hand (so put away that electric hedge trimmer!). Each branch or stem is cut individually, with cuts carefully placed based on bud growth. The most commonly-used tools are pruning shears (also called secateurs or hand pruners), loppers, and pruning saws.
Pruning results in a more natural look and is generally better for the health of the plant. It allows you to make more judicious cuts to shape the plant and address specific issues, such as diseased or damaged branches. And by letting light into the interior of the shrub, you encourage growth throughout the entire plant, not just on the branch tips.
It does take some education, practice, and patience to do it right – but it’s well worth it!
You can find much of the information you need right here in the Member section of the Complete Pruning Guide. And if you’d like more instruction, take a look at our online course, Pruning With Confidence.