In ancient Rome, transforming plants, trees and shrubs into exotic shapes was reserved for the wealthy, whose slaves perfected the art of topiary. Although topiary has a checkered history, it remains a popular art, especially in Europe. Lavender is a suitable choice for topiary because it is evergreen, versatile and lends itself to shaping.
The Cloisters Museum and Garden is part of The Metropolitan Museum of Art in New York and depicts the art and architecture of medieval Europe, dating back to the 12th century. The collection of artefacts within the Cloisters includes more than 5,000 works of art. Cotton lavender (Santolina chamaecyparissus) is among the topiary container plants grown in the Cuxa Cloister.
Cotton lavender foliage is grey in colour, unlike other topiary favourites such as bay laurel and myrtle, although all three are evergreen herbs. It is slow growing, usually reaches about two feet tall and prefers sunny and dry conditions. Cotton lavender is also fragrant.
English lavender (Lavendula angustifolia) is a popular topiary choice, particularly for a wire frame. The stem of this perennial plant eventually thickens to look like tree bark. English lavender takes about a year to grow to a foot high. Use a wooden stake to secure the plant for sturdy growth. Its ideal growing conditions include full to partial sun and moist, well-drained soil. Once the plant reaches about a foot high, cut the top to stem further growth. Instead of growing upwards, the plant then spreads outwards and forms a topknot that you shape into the topiary form you prefer.
The green and purple summer leaves turn to green and silver in the winter, with a stippled appearance. English lavender is famous for its blue and purple flowers, usually blooming in the summer months. This particular type of lavender fills the garden with its sweet scent, and is also popular in potpourri and sachets.
Lavandula stoechas is called French lavender, or Spanish lavender. This perennial features purple flowers that bloom in the summer and attract butterflies -- it is called butterfly lavender for this reason. As a topiary choice, French lavender requires regular trimming work, because the spent flower spikes should be removed after the blooming period. It also needs good drainage and shelter from the cold.
The Australian bred variety, Boysenberry Ruffles, makes an ideal container topiary. It grows to about 18 inches tall, and prefers dry conditions, good drainage and lots of sunshine. Make sure this lavender plant does not sit in water at any time. Boysenberry Ruffles have pink flowers and fragrant, grey-green leaves.