How to Design a Spiral Evergreen

Select a young, conical evergreen shrub or tree. Boxwood, juniper, Eastern Red Cedar (Juniperus virginiana), privet, pyracantha and yew cultivars are among the best choices for a spiral-shaped topiary.

Avoid any tree or shrub with structural flaws that will affect your final design, such as a spindly or weak top or damaged areas that won’t fill in with leaves or needles. Choose the healthiest individual plant or plants available.

Even out the surface of the shrub with hedge trimmers, if needed, being careful not to remove too much vegetation. A smooth, even surface will make it easier to create a symmetrical shape.

Tie one end of colored vinyl flagging tape to the top of the tree and unwind the tape roll around the tree and down, to create a spiral stripe. Make sure the distance between the sections of the spiral is about equal -- 8 to 10 inches for a tall topiary.

Clip a narrow stripe just above or below the tape – whichever seems easier to you – using grass shears. Remove the tape, and go back and re-trim any areas that seem too thin. You now have a template for your final design.

Cut away all the foliage along the template line, top to bottom, working at a consistent angle or cutting straight in, perpendicular to the plant. Remove all leaves or needles, small stems and branches you encounter along the line, all the way down to the trunk.

Stand back and study your spiral design, looking for any irregularities. Clean up these rough spots. Finish by rounding off the outer edges with the grass shears or hedge trimmers, removing no more than 1 inch of foliage.

Cut off the top off your topiary shrub or tree to maintain your sculpture at that height. Let it grow two or three years longer if you want a taller topiary. Extend the spiral upward every year the topiary is still growing.

Maintain your spiral topiary by trimming it again with grass shears at the beginning of every summer, just as the year’s new growth starts to toughen up.