The best topiary plants among trees, shrubs, and herbs bear small leaves, like to be sheared, grow quickly, and have a dense branching pattern. But, as always with plant selection, stay realistic yet open-minded: You may decide to give up one of these features to grow a plant that has another quality you admire, such as being scented or easy to grow.
They’re poisonous: Avoid growing them if children will be playing outdoors or if you let your dogs loose in the yard. They grow slowly.
But if you don’t have kids or pets in the yard and do have some patience, yews (zones 4 to 7) make excellent topiary plants. T. baccata ‘Repandens’ is a great pick for a long-and-low topiary shape: It’s 2 to 4 feet high and 12 to 15 feet wide. ‘North Pole’ (zones 3 through 7, full to partial sun) is a good cultivar if you need a topiary that’s taller than it is wide (10 to 15 feet tall x 5 feet wide) but that isn’t too tall. ‘Golden Globe’ (zones 4 to 8, partial to full sun, 4 feet tall and wide) is suited to an entirely different type of topiary. It offers a different color (golden foliage) to boot. Grow the ‘Otto Luyken’ cultivar (zones 6 to 8, full sun to partial shade) for a small topiary: It stays smaller than the species plant. It may eventually get bigger than its listed size (3 to 4 feet tall by 6 to 8 feet wide), but only after many years (prune to keep it from exceeding these limits if you’d like). L. japonicum is indigenous to Japan. It’s evergreen, but it’s suited only to zones 7 to 10. The bush becomes 6 to 12 feet tall, with a spread of 6 to 8 feet. Both are invasive in parts of the U.S. Those with an artistic bent can take the edging-plant idea a step further and build a knot garden, which is an intricately designed garden with plants arranged to create an interlacing pattern, sometimes with fanciful topiary and carefully tended paths. Outdoors, English ivy (zones 4 to 9, partial to full shade) can put out vines 50 feet long. Where English ivy is invasive in North America, you can grow it as a houseplant; give it lots of indirect lighting and keep the temperature around 70 degrees Fahrenheit.
