Plant choices in the landscape depend entirely on matching the new addition to growing conditions. The primary concern lies in choosing a plant based on sunlight requirements. Sunlight requirements relate directly to how plants use the sun to grow. Plants absorb sunlight through leaves to convert to carbon dioxide for use as food. This product then is expelled as oxygen into the environment. Plants receiving inadequate amounts of this essential food won't thrive in the garden. Sun vs. shade plants use sunlight differently by adapting to diverse growing conditions.
Types of Sunlight
One confusing part of gardening lies in understanding exactly what type of sun a plant needs. Grower instruction labels often simply denote sunlight requirements on the label without fully explaining what these terms mean in the real world. Planting conditions rarely conform to the perfect instance that explains sunlight conditions. All three terms refer to exposure to the sun for some part of the day. Full sun signifies garden areas receiving at least six hours of direct sun each day. Partial sun areas feature four to six hours of direct sun each day. Partial shade differs very little from partial sun exposure and features two to four hours of sunlight each day. Full shade experiences no direct sun or less than two hours each day. Shade areas include dappled sunlight experienced under a spreading tree canopy.
Sun plants include flowers, vegetables, shrubs and trees that thrive in direct or moderate light exposure. These types of plants don't respond well to decreased sun and exhibit noticeable symptoms of stress. These include wilted leaves, incidences of infestations and die-off of the plant. Sun plants have different leaf structures than shade-loving plants. Leaves tend to be thicker to increase light absorbency. Many plants make minute adjustments to leaf thickness in response to the growing environment.
Shade plants adapt to reduced-light conditions with thinner leaves and modified leaf structure. Shade leaves produce chlorophyll in higher degrees than sun-tolerant plants. Chlorophyll serves as the primary molecule that absorbs sunlight and converts it to food for the plant. This molecule also causes the changing colors of leaves in the fall as chlorophyll levels decrease at the end of the growing season.
Sunlight doesn't act alone to provide fuel for a plant. Plants also require adequate water and nutrients from the soil to produce stunning foliage and flowers. Gardening to provide all these things becomes a balancing act for the plant enthusiast. Both sun and shade plants cannot tolerate elevated exposure to water. Excessive water from rain can damage plants and encourage mold spore growth on leaves. Spores spread readily in the garden environment with breezes and can create a nightmare for gardeners. Gardeners should water sparingly at the base of sun and shade plants to limit damage to the leaves.
Shade and sun plants differ greatly in their adaptations to absorb sunlight. For this reason, gardeners should choose plants for placement in the landscape paired with a plant's specific needs. Monitoring the landscape to understand sun availability will help in choosing appropriate plants. Remember that sunlight exposure changes with the seasons, so adjust your planned garden design to fit the needs of your plants rather than personal preference.