Aesthetic preference for different green boundary wall designs in Colombo, Sri Lanka.

Abstract

In many urban settings, unconventional greening solutions like greening boundary wall facades are gaining popularity. Recent studies have shown that having green walls is mostly motivated by their aesthetic appeal. However, no research work has focused on identifying what kind of configurations, and species are aesthetically preferred. This study investigated the aesthetic preferences for 56 different green boundary wall designs that were made for 11 different green wall configurations that were suitably planted with 15 different plant species. 516 participants in a photo-simulated psychological experiment assessed the photo-stimulated designs for their overall aesthetic preference as well as five other independent characteristics that could affect their choice of these designs. The most favoured living walls included Ficus pumila, or creeping fig, according to the results. The desire for living walls was higher than that for green facades. All other designs were thought to be better choices for boundary walls, except the greening options of ground coverings with the species Roheo or Ferns. Adding Thambergia, Passion Fruit, Cat’s Claw, Galepemia, and Ixora to boundary walls can increase preferences. Green wall configurations having less vegetation coverage and more exposed boundary wall surface areas received the least preference. Further attractiveness and suitability of the plant species were identified as factors influential on the preference. Given their functional, environmental, aesthetic, and financial advantages, living walls planted with Creeping Fig species can be suggested as the most practical choice for boundary wall greening among the design alternatives examined. The design alternatives proposed can be used to improve the aesthetic appearance of urban roadside landscapes as well as to bring restorative benefits to gardens of hospitals and elderly homes.