Growth Considerations

• The best shrubs to use for topiary purposes are ones that grow quickly. Depending on the variety of shrubs you plant and the desired size and shape of your finished topiary design, these topiary plants may require between three and 10 years to complete, according to Iowa State University Extension. Choosing shrubs that display a fast rate of growth allows you to complete the desired design sooner. Growth rates may vary among similar cultivars. When selecting shrubs for topiary purposes, check the care label for growth habits, choosing those with a medium to fast rate of growth.
  
  

Appearance

• Shrubs used for topiary purposes also require dense growth and abundant foliage. Shrubs that contain masses of tiny leaves or tight clusters of thick needles make the best selections for trimming and shaping into topiary designs. Choose shrubs that grow to mature heights several inches or feet taller than the height of your intended shape. This allows for even fullness throughout your topiary, including the area at the very top.
  
  

Varieties

• Yews are one of the most common types of shrubs grown for topiary use. Taxus is the botanical name for these shrubs, which contain dark evergreen, glossy needles. Holly, also called Ilex, as well as boxwood, which goes by the botanical name of Buxus, also exhibit suitable growth habits for topiary purposes. Yews and holly plants grow as both shrubs and trees, making them suitable for tall topiary designs. Bay laurel and privet are also appropriate for growing as topiary plants.
  
  

Considerations

• Creating topiary designs often requires an abundance of trimming, making it important to select shrub types that can withstand heavy pruning. Although you can form topiary completely through pruning techniques, topiary frames allow you to easily direct the plants growth and maintain the intended shape. When selecting new shrubs to grow as topiaries, choose ones that fit easily under your topiary frames. As the shrubs grow and fill in the topiary frames, you can maintain the shape by constantly trimming them back to the edges of the frames.