How to Tips on Trimming Juniper Trees Into Different Shapes

Carefully trimmed junipers look like leafy green sculptures.

Versatile juniper trees may be trimmed and trained into specific shapes, allowing you to give your landscaping a formal or whimsical look. Trimming juniper trees isn't quite as easy as envisioning the shape you want and cutting away. Pruning must be done at the right time of year, with the proper amount of finesse, to prevent damage to the juniper itself. With careful trimming, it's possible to create a wide variety of shapes with juniper trees.

Things You'll Need

• Pruning shears
• Bucket
• Bleach
• Plastic/wire topiary form
• Neon spray paint (optional)

Instructions

1. Wait until late winter or early spring to prune juniper trees annually. The best time to prune is when the plant is not producing new growth.

2. Fill a bucket with nine parts water and one part bleach. Dip pruning shears into the solution prior to making each cut on the tree. The bleach water will kill germs and bacteria that may spread disease throughout the tree.

3. Cut away all broken, diseased and dead branches from the juniper with clean, sharp pruning shears. Cut these unhealthy branches back to the trunk.

4. Purchase plastic or wire topiary forms at a home and garden store. The forms serve as a guide for your juniper. Forms may also be hand-made by bending and shaping metal wiring, but gardeners are advised to spray-paint them a bright neon yellow or orange color before placing them over the juniper. Plain wire forms are difficult to see and easy to cut through.

5. Place the form over the juniper, centering it around the main trunk.

6. Prune any branches that are growing outside the bounds of the form, cutting them back to the nearest branch joint that is within the desired shape. Avoid cutting branches larger than 1/2 inch to 1 inch in width when possible, as these will be hard on your shears and may even cause them to break.

7. Prune away lower branches of the tree only when they are approximately 1 inch in diameter. Excessive trimming around the bottom of the tree could weaken the trunk.

8. Make a classic "topknot" topiary form by slowly pruning away the lower branches of the juniper until only a bushy growth remains at the top. Trim the foliage at the top in a circular form. Remove the bottom branches of the tree over time, clearing away the bottom 1/4 of the branches yearly until the desired shape is achieved.

Tips & Warnings

• Start pruning juniper trees when they are still young to train the growth into the desired shape.

• Remove no more than 1/3 of the total branches from the juniper. Removing too many branches may be fatal to the tree.

• Prune the top of the central trunk only as necessary to reduce the height of the juniper.

References

• Texas AgriLife Extension Service; Follow Proper Pruning Techniques; Douglas F. Welsh, et al.
• Fort Valley State University: Arborvitae, Juniper, Pine Pruning
• University of Kentucky College of Agriculture; Pruning Landscape Shrubs; R.E. McNiel, et al.
• French Gardening: The Ancient Art of Topiary
• Front Range Living; Topiary -- When Artifice Becomes Art; Niki Hayden

Resources

• University of Missouri Extension; Pruning Ornamental Shrubs; Christopher J. Starbuck
• Purdue University Cooperative Extension Service; Pruning Ornamental Trees and Shrubs; Michael Dana, et al.