Yews (Taxus spp.) are slow-growing evergreens with 1-inch long needles. These dark-green, dense plants range from low growing shrubs to upright, conical trees. Depending on the specific cultivar, yews are hardy in U.S. Department of Agriculture Plant Hardiness Zones 3 through 9a. Growing well in both full sun and partial shade, they can withstand a variety of soil types as long as the media is well-draining. Upright growing yews require pruning to keep their pyramidal shape defined.
Prune pyramidal yew trees in the early spring, while the plants are still dormant. Walk around the tree, mentally drawing a downward slanting diagonal line over the surface of the foliage to mark the desired finished shape of the tree, or perimeter line. Always create a perimeter line defining a wider base and narrower top and removes of no more than one-third of the yew's branch length.
Tie one end of a string to the top central leader of the yew and pull it downward along the desired perimeter line, keeping it taught against the foliage. Stake the bottom end of the string to the ground using wooden stakes so that it remains in position, marking the trim line. Repeat with three or more additional strings spaced evenly around the plant.
Look for broken, damaged or diseased branches and remove them first, cutting back to a growth point or lateral shoot located in healthy, undamaged wood using a pair of scissor-type hand shears. If the branch is severely damaged or diseased, remove it entirely. Sterilize the shears' blades after cutting off diseased branches by soaking them in rubbing alcohol for 3 to 5 minutes.
Prune away the ends of the branches that extend past the perimeter guide strings. Cut back each outlying branch to growth node or lateral branch just inside of the perimeter line. Make the cut at a 45 degree angle, one-quarter inch above the node or lateral branch. Work your way in a circular motion around the yew. Stop periodically to step back and observe your work. Look for branches that you may have missed and ensure that your work is even and aesthetically pleasing.
Remove any suckers growing straight up in the yew's canopy. Cut each sucker off at its base, one-quarter inch above the surface of the trunk or main branch from which it is growing. Prune away any branches that are crossing and rubbing against other branches.
Gather up the removed branches and rake up any fallen needles. Discard the loose plant material in a trash bag.
Untie the strings from the top of the tree and the stakes. Remove the stakes from the ground. Walk around the tree one last time to ensure that the shape is even and that you have not missed any outlying branches.
Prune the yew a second time in mid-summer to remove any branches extending past the perimeter line or any fast-growing suckers growing taller than the central leader. Cut the branches back to the perimeter line, just above a growth point.
Things You Will Need
- Wooden stakes
- Scissor type hand shears
- Rubbing alcohol
- Plastic trash bag
- A yew's foliage, stems, bark and seeds are poisonous to humans and pets. Beware of planting yews in areas where young children and pets are present.
- Stockbyte/Stockbyte/Getty Images