Just like the architectural elements that make up built space - floor, walls and ceilings - natural elements are also capable of creating spaces in large-, medium- and small-scale areas, in places like public and residential gardens.
According to Brazilian landscape architect Benedito Abbud, "Landscaping is the only artistic expression in which the five senses of the human being participate. While architecture, painting, sculpture and other visual arts use and abuse only the vision, landscaping also involves smell, hearing, taste and touch, providing a rich sensory experience by adding the most diverse and complete perceptual experiences. The more a garden can sharpen all the senses, the better it fulfills its role. " 
Below we list some of the key elements of landscape planning and design. See the principles and learn why you should never randomize the placement trees!
Nature as Architectural Elements
As with architecture’s constructive elements, vegetation can also provide equivalent spatial conditions with a specific use of trees, shrubs and different species of plants. Trees can be associated with similar spatial qualities as pillars and tree crowns can relate to conditions provided by roofs and ceilings. Shrubs tend to establish a protective feeling and different types of grass and rocks relate to flooring.
A specific use of vegetation or rocks and stones in landscaping will create different delimitations of the spaces in horizontal planes (such as the floor and ceiling) as well as in a vertical plan (walls, fencing or pillars).
Open Spaces and Free Areas
While some areas will use vegetation to provide shade or to act as a barrier, it is essential to incorporate free areas (clearings) that can be activated by the users in a variety of ways, giving people the freedom to relax, play sports, picnic or spend time with their pets.
Large free spaces will present solar challenges, so the use of wet areas such as small lakes or water mirrors can help. Shaping the vegetation masses to influence or channel predominant winds can also ensure more favorable conditions.
Alignment and arrangement of trees
One of the key points of landscape projects is the creation of areas for different use and activities. A determined placement of the elements will create different atmospheres and may transform a determined zone into a clear and defined space with a particular use, or as well can leave the space open for the improvisation of activities like most public parks do.
Here are some standard templates of tree layouts and their effects.
Linear layout: If used in a linear way, trees or species of the same height tend to create vertical planes, acting like a succession of pillars or walls. You can play with the foliage density of the trees and their heights to have different spatial results.
In the case of species with larger treetops, this configuration can resemble natural ceilings and may cover large areas with less “pillars”. If a less monotone result is desired -or a more natural feel- the use of several species of trees and different heights will tend to create variations in the perception of the space.
Triangular layout: If positioned triangularly, two (or more) rows of trees should aligned together and interspersed in a 60º angle. The result is a wide wall that can provide lateral barriers (visually and physically) through the mass of trunks and canopies. Frequently used in the perimeter of urban parks, this layout also gives a natural acoustic barrier, depending on height and density.
Curved layout: Curves and the creation of serpentine lines in tree arrangement creates a sense of movement. This model is often used on the edges of water surfaces or in the creation of key areas of interest with a less structured display that invites to take a walk through.
ZigZag layout: This alignment consists in a single row of trees arranged at a 60º angle. This layout transmits the idea of movement and creates center spaces where furniture and equipment can be placed.
While decreasing the acoustics of the place by separating and enclosing, it can also broaden the projected views.
Make sure you never randomize the placement trees, as it may cause problems during the construction and planting process and also, in the final intention of the project.
In our next article, we will talk about the configuration of visual landmarks and axes, as well as the different design scales used in a landscaping project.
 ABBUD, 2006, p.15
ABBUD, Benedito. Criando Paisagens – guia de Trabalho em Arquitetura paisagística. São Paulo: Editora Senac, 2006.