How to Make a Double Ball Topiary Tree

Widely regarded as a plant style for formal gardens, topiary can add a touch of whimsy and fun to any gardening style. Topiary dates back to ancient Rome and became increasingly popular throughout Renaissance Europe. Today, evergreen shrubs are pruned into a variety of shapes, include balls, cones, spirals and even fun animal shapes. A double ball topiary appears as a bare trunk with two ball shapes along the length of the trunk. The ball shape is easiest to achieve with dense, upright evergreens, such as myrtle (Myrtus), English yew (Taxus baccata) and green mountain boxwood (Buxus sempervivens).


Measure the height and circumference of the mature, upright evergreen shrub and use the size to determine the size for the two balls. Pyramidal evergreens tend to get narrow at the top, so either make the ball at the top of the topiary smaller than the bottom ball or trim extra foliage from the bottom ball to make two balls of the same size. Leave at least 1 foot of space between the two balls for better definition.


Form two circles for each topiary ball from heavy-gauge galvanized wire, such as 16-gauge or stronger. Make each of the two wires for each ball identical, to form a perfect sphere shape; if the two balls will be different sizes, make a total of four wire circles, two circle frames for each ball.


Fit one wire frame for the bottom ball over the shrub so it rests on the branches in the center of what will be the bottom ball. Place the wire perpendicular to the trunk with the excess branch length protruding beyond the wire circle.


Fit the second wire circle frame so it runs vertically with the top and bottom of the frame resting against the trunk.


Trim the branches back to the wires, using the wires as a guide and only trimming the narrow line directly against the wires; use a combination of hand shears for foliage and bypass pruners for snipping through tough branches.


Turn the wire hoops on the bottom ball so they run diagonally across the shrub, with each hoop positioned in the center between the trimmed vertical and horizontal lines. Trim the foliage that protrudes beyond the wire hoops to finish the basic shape of the bottom circle.


Remove the wire hoops and trim the rest of the bottom ball shape, using the cut lines as a guide for the branch length. If desired, reposition the wire hoops on the shrub and continue to use the wires to guide your cuts.


Fit the two wire hoops for the top ball over the tree and put them in position with one vertical and one horizontal hoop.


Cut all the branches back to the trunk between the top of the bottom ball and the bottom wire for the top ball; this piece of bare trunk separates the two balls. Alternatively, you can trim the shrub with the two balls stacked on top of each other with no separation between the two shapes.


Trim the foliage on the top ball back to the horizontal and vertical wire hoop frames. Turn the hoops diagonally and trim the foliage back to the wires. Trim the rest of the foliage to finish the top ball shape.


Step back from the shrub to locate any branches you might have missed and trim these to perfect the spheres. Cut the pointed top from the shrub if it remains after shaping the top sphere. Remove any excess foliage under the bottom sphere.


Clip the balls about once monthly or when new growth develops, to maintain the spherical shape. Avoid trimming the plants in the heat of summer when pruning can put too much stress on plants.