Full Sun, Part Sun, Part Shade, or Full Shade?
A plant feeds and consumes energy from the sun through a system called Photosynthesis. Plants take in the sun’s energy and converts its energy to keep itself alive. That is why plants grow towards the light. Now that you know that, we all see light requirements for various plants saying full sun, part sun, full shade, part shade; what’s the definition of all those and the difference? It is simple to know all the light needs for plants.
Part Sun vs. Part Shade
When I first saw these and was confused, I asked myself – are they the same? Does half the plant need to be in sun and the other half in shade? Partial sun or partial shade labels both mean a plant needs three to six hours of sun each day, but they carry a different emphasis. Partial shade plants need protection all day except those three to six hours per day. Partial shade plants often do best when they receive direct morning sun, but stay sheltered in the afternoon. The morning sun is less harsh in the morning compared to the afternoon sun, pretty much why we need good sun block in the afternoon sun because we all will get burned more easily with the intense afternoon sun. Partial sun plants, greater emphasis is placed on it receiving at least the minimum three hours. When you see “part sun” used, the grower is stressing that the plant requires at least three hours of sun and will likely do better with closer to six hours. When you see “part shade” used, the grower is stressing that the plant should not receive more than six hours of sun and will likely do better with less.
Full sun plants thrive when they receive unobstructed, direct sun all day. The more natural sun they receive, the better they do. As a minimum, plants in this category need at least six hours of direct, full sun each day to function effectively. If they don’t receive enough sun, they often lose their normal color and fail to bloom or bear fruit. Full sun is probably the trickiest level of exposure because while many plants need full sun to set buds and flower, some cannot handle the intense heat and/or dry conditions that often come with that much sunshine. One way around this is to plant the more sensitive plants where they will get more morning sun, than afternoon. It’s cooler in the morning and as long as the plants get at least 6 hours of direct sunlight, they should grow well.
Full shade plants perform best when they receive less than three hours of daily sun. Even a spot of all day sporadic filtered sunlight will work, meaning plants set under large trees with broken sunlight reaching the ground. If in an area of that three hours of direct sunlight, morning sun that is less intense than afternoon is best.
There are other obvious factors that affect how plants react to sun. Knowing where you live is helpful as well. Latitude, elevation, time of year and time of day all matter. The farther south you go in North America, the more intense the sun becomes. The closer you are to the sun, the more potent its rays. In midsummer, noontime sun burns hotter than in midwinter. Morning and late-afternoon rays are gentle compared with early afternoon. Plants that tolerate full summer sun in northern climates may need afternoon protection in southern and western regions. These technical details aren’t as important as the general understanding of full sun, part sun, full shade and part shade mentioned above. You are now ready to choose what plant is right for that area in your landscape that receives full sun, some sun, or no sun!