Full sun, partial sun, partial shade, full shade, direct sun, indirect sun, filtered sun. All of these terms are widely (and sometimes carelessly) used to describe the light preferences of landscape plants. Confusing? yes. Important? Definitely.

One reason that plants perform poorly in some landscape locations is that they are planted in an area that does not meet its light preferences. I say &uot;preference&uot; because most plants will tolerate a lot of extremes when it comes to light, but most definitely perform best in one or the other or half way between.

Obviously, plants cannot move. If we don’t like a hot sunny location, we simply move to the shade to cool off. Or vice versa. Plants are stuck where we place them and must cope with the light situation.

In order for plants to perform best, you must understand what type of light a site receives and what type of light a plant prefers. It just doesn’t work well to go and buy plants to put in your yard unless you know where you are going to plant them and what the light situation is. It’s like the square peg in the round hole theory. With a big hammer, the square peg will go in, but a round peg goes in much smoother.

To do a thorough site light analysis you must first understand the movement of the sun, or if you believe Galileo, the earth. If you notice, the sun changes angles constantly. In the winter, the sun is very low and may not rise much above the tree line. In the summer, the sun seems like it will never go down.

Since the sun angles change with the seasons, how do we remember where it is going? A professor of mine in college summed it up nicely. The sun behaves like a rich person from New York. It goes south in the winter and north in the summer.

The north side of a solid object (house, wall, fence etc.) will rarely get any sun, while the south side will be set on broil. With the sun moving from east to west, the cooler morning sun will be on the east side of an obstruction, while the hotter afternoon sun will be on the west side.

Light requirements are usually divided into categories. These terms generally refer to the prime growing season of March through October. However, keep in mind that areas can change with the seasons. This may be due to the sun’s angle or to other factors like deciduous trees. In the winter, an area under a tree may have full sun. Yet, in the spring, after the tree leafs out, the area may be total shade.

Full sun generally means that an area receives direct sunlight all day. Direct sun means that it is not filtered in any way by leaves or other obstructions. A plant that grows best in full sun will need these conditions and many plants do perform best in full sunlight. An example of this would be a garden out in an open area with no obstructions.

A plant that grows in part sun requires at least six hours of direct sunlight between the hours of 10 a.m. and 6 p.m. Many times a plant will be labeled with a full sun and a part sun sign. This means that the plant requires a minimum of six hours of direct sunlight to flower and will probably perform better with even more sun.

Full shade is a site that will not receive any direct sunlight. This might be a site on the north side of a house or other obstruction. Under many dense shade trees, live oaks, or wooded areas may also be a shaded location. A true full shaded site may limit your plant selection choices, but in no way does it prevent you from planting a garden. Many plants are available that thrive in the shade. In fact, shade gardens can be magnificent with the right plant selection.

Partial shade can be described as an area that receives, or a plant that prefers, neither full sun or full shade. These areas may get filtered or dappled sunlight throughout the day, or they may get less than six hours of full sunlight. Usually plants in partial shade need protection from the mid-day sun.

Often times plants may do well in full sun to partial shade or from shade to partial sun. Keep in mind that morning sun is usually less harsh than the afternoon sun.

Take the time to do a light evaluation of the areas in your yard. Likely, you may have many different exposures. Likewise, when selecting plants make sure you know what type of light they prefer. Most will have tags indicating light preferences. If they don’t, ask your nursery professional for help and advise.

A plant in the right light location will be much happier. Happy plants smile often in the form of flowers.

Gardening Miss-Lou Style is a weekly column written by Traci Maier of Natchez. She can be reached at 445-5181 or by e-mail at ratmaier@iamerica.net