Let There Be Sun

A deciduous woodland has sunlight in the understory

A well-managed pineland is sunny

One of the most important decisions one can make in designing a landscape revolves around sunlight. Too often in my own experience, I have "protected" plants from the sun and it always has failed me. The reason is that sunlight feeds plants. It's not nutrients in the soil nearly as much as it is sunlight itself. Nutrients are important for a great many things, but most are only really important for the role they play in facilitating photosynthesis. It's really a simple equation: sunlight plus water and carbon dioxide creates a simple sugar - glucose, and that sugar gets manufactured in the plant to form every carbon-based molecule necessary to the plant's survival. Cell walls, proteins, fats and everything else a plant requires comes from sunlight and the carbon in carbon dioxide. Once we understand this, we understand the role sunlight plays in the growth and health of our plantings.
Protecting plants from sunlight is like protecting them from the one thing they need to thrive. Plants that don't get adequate sunlight, fail to thrive. First, they quit growing in order to protect themselves from losing the energy they need to support their basic metabolism. The last thing they will do is flower and set fruit. Why bring children into a world that lacks the basic essentials needed to survive? It is true that some plants have evolved to succeed in low-light situations, but they are few and far between. Phalaenopsis orchids, for example, will burn up if grown in direct sunlight and some others need protection from the most severe sun during midday, but every plant needs some sunlight to survive. Over the years, I've killed far more plants from "protecting" them than I have by giving them too much sun. Understory trees and shrubs that I had planted in my former woodland landscape are excellent examples of my past failures. Here, I've planted my 3 species of native azaleas (Rhododendron spp.), my serviceberries (Amelanchier arborea) and my silverbells (Halesia spp.) in locations where they receive hours of direct sunlight. In my former landscape, they survived, but they rarely, if ever, bloomed the way they do in nature.
I do not grow my understory trees and shrubs for their foliage; I grow them for their pollination services and the fruit they should produce to feed my birds. Where I've planted them should do that. What this means is that I must carefully consider the location of each before I plant. Planting design seems often to be overlooked. We consider space - where we have room, for example, above where they will receive the sunlight they need. It is critical that we understand the sunlight patterns in our landscape before we plant as well as the future conditions that will be created by our plantings. In a perfect world, we would study the sunlight patterns in our landscape for a year before we even begin to plant. I'm not that patient, but I recognize that the southern exposure of my plantings will receive more sunlight than my northern one. I understand that my canopy trees will shade the understory more in the areas closest to their trunk than on the outside of their future canopy and I know that deciduous plants will allow sunlight into the understory for the critical period of time when many of my plants need full sun in order to bloom and set fruit. 
I hope that I've done things better with this landscape than in others I've planted in the past. I have planted only one tall tree, a basswood (Tilia americana) to anchor this new developing woodland. Everything else will form an understory that has branches in some sunlight during the summer and all of its stems in full sun during winter and early spring.  I've expanded my wildflower areas to the south of these woody plants and they should get ample sunlight there even as the woodland matures over time. In the front yard, where I've placed my wildflower meadow. I've added some small trees and shrubs, but all of them are on the north side of my wildflowers and native grasses. These will not shade those plants that prefer full sun to thrive. On the south border of my backyard, I've added more small trees, but they are at the opposite end of the property and will never get large enough to shade the other end.
Landscape design is a critical feature and it needs careful consideration if a landscape is to succeed in achieving its full potential and the most important element of design is understanding the sunlight patterns that exist and how they will change as we put plants in the ground. Evergreen trees with wide crowns, like live oaks (Quercus virginiana) and southern magnolia (Magnolia grandiflora) are beautiful, but have a much bigger impact on a landscape than a narrow-crowned tree. A tall tree, by simple geometry, will have a greater impact  than a shorter one and a deciduous tree will play a much different role than an evergreen. All of these considerations need to be contemplated before one goes about purchasing one's plant palette. Too often, we simply purchase those species that we most desire without this consideration and/or we begin planting by putting them into the ground where there is space to do so. I've been as guilty of that as anyone in my past. I hope I've learned a bit more this time. There's a whole bunch of plants that I love and wish I had room for. My current plan leaves some of them out. It makes me a bit sad to have done this, but what I've chosen should work better this time. I guess that time will tell.