Tuesday, July 5, 2011

Espalier: The Art of Plant Training by Elaine Lockey

Espalier at Denver Botanic Gardens
Espalier, pronounced esp-al-ee-er or esp-al-ee-ay, is the practice of training and pruning a plant to grow on a flat plane against a wall, fence or building.  This can create a beautiful focal point in a garden, can save space in small areas, and help fill in space if you have a large wall or fence that you want to hide.

Espalier can be informal or formal and there are several common forms practiced.  Certain plants respond best to certain types of espalier as well.  Informal espalier can be as simple as a vine climbing up a wall to a pyracantha hedge that is pruned in a flat plane but is allowed to branch where it wants vertically and horizontally.  Formal designs can be like the French palmette verrier in which a plant, commonly a pear tree, is attached to a frame that helps to shape it into the desired structure.  This particular one looks like a box shape or candelabra. This enables the pear tree to grow wide but the height is limited.

Simple backdrops work best to highlight the trained plant. When thinking about site selection look for walls or fences that would be enhanced by the espaliered plant. Normal growing conditions should be provided such as proper soil, water and light. Often a south or east-facing wall is a great place to put a plant but keep in mind that walls also add extra heat and that can be a problem in winter for plants that are susceptible to winter injury.

Espaliered fruit trees can produce heavy fruit loads and can be positioned in areas such as against a south-facing wall where they receive more sunlight and warmth.  Fruit trees and most other plants need to be attached to a trellis or the fence or wall in some manner to lend the branches support. With informal design a frame may not be needed, but supports might be. Plants should be spaced at least 6” from walls to allow for air circulation and to reduce potential pest issues.

photo courtesy of colonialsense.com
You can buy plants that have already been started with a trellis so that all you have to do is transplant them. Untrained plants can be started fairly easily as well with a little more time upfront to get them ready. Prune new plants sparingly until they are established.  Plant limbs are most flexible in the summer so this is the best time to train new twigs to your supports. Espaliered plants must be pruned and trained annually. There are numerous resources available to aid in teaching this art form so I won't go into the actual pruning and training practices here.

Plant choices should be based on the type of espalier design you want to achieve and also in selecting plants with interesting foliage, fruits or flowers.  Some common plants used are pyracantha, Japanese maple, redbud, forsythia, crabapples, viburnum and yews. Many of the various dwarf or semi-dwarf fruit trees can be trained for a beautiful and edible espalier.

Once you have an idea of where you’d like to put your plant and if you want a fruit tree or not, you can begin making your selection at the nursery of the species. Then the hard work begins -but you will have a true conversation piece and work of art that you’ll be proud to show off!