How to Prune Korean Spice Viburnum
There are more than 150 species of viburnum. Korean spice (Viburnum carlesii) is covered in pinkish-white flower clusters in the spring. They smell sweet and are the size of grapefruit. The shrub is perfect for many landscapes because it only grows to a height of 6 feet and has an equal spread. The green leaves have awesome autumn color, turning scarlet in mid-fall. Prune Korean spice viburnum to maintain its shape and improve its health.
Prune Korean spice viburnum immediately after flowering, in the late summer or early fall. They bloom on last year's wood, so pruning them in the spring or late winter will result in removing the very buds that are getting ready to open.
Shape the viburnum by heading it. This occurs when you cut off or pinch back the ends of shoots and branches. New growth will come in thicker. Cut above the node, where leaves, buds and stems attach to the branch. If you prefer to do it by hand, pinch off the ends with your thumb and index finger.
Remove weak, diseased and dead branches as soon as you notice them. Cut them at their base, where they meet healthy wood. This will thin out the Korean spice viburnum and keep disease from spreading.
Identify unwanted shoots in the middle of the Korean spice viburnum. Look for older branches that are clogging up the shrub, preventing air from circulating and sunlight from reaching other branches.
Cut off unwanted stems, shoots and branches at their base by removing them inside the bush, where they meet other branches. Cut them at the thick section next to the joint. Tissue will regrow over the wound.
Thin out weaker, young shoots that are growing at the bottom of the Korean spice viburnum. Snip them off where they meet the main trunk of the shrub.
Make clean cuts. Always cut the Korean spice viburnum back to living, healthy wood.
Don't remove too much of the bush every year; it will result in damage. Avoid leaving behind jagged, torn edges.