I.What is shade? Types of shade
Most sources agree on 5 general categories of shade: partial, light, medium, full and dense shade.
1.Partial shade (open or semi-shade) is the lightest, most open type of shad and the easiest to work with. Partial shade describes areas receiving 3-6 hours of sun/day, either in the morning or afternoon, or areas of highly dappled sun all day.
2.Light shade is found under the branches of slender trees or under mature trees with a high lacy canopy. Dense trees or buildings some distance from the garden can also cast light shade. A light shade garden may receive full sun for one to two hours during the day, but bright light the remainder of the time. Light shade can also be defined as full shade for 2-3 hours/day and partial shade the rest of the day.
3.Medium shade is found under trees with branches 20 feet or more off the ground and a fairly open canopy. Medium shade also occurs where there is reflected sunlight or shade from a north-facing wall with no other obstruction. It may also be defined as an area shaded during the four to five brightest daylight hours, but receiving sun the rest of the day.
4.Full shade exists beneath branches of mature trees with dense foliage, large leaves and a spreading canopy. Full shade may also be found at the base of a tall north-facing wall or hedge. This type of shade is excellent for native woodland plants.
5.Dense shade is the deep, cool shadow cast year-round by mature evergreens or a nearby building.
II.Factors to Consider
Quality of shade is determined by a variety of factors, not just the daily amount of sun. The time of day your garden is shaded is important, afternoon shade is different from morning shade. Whether the garden is shaded by trees (and what kind of trees) or by buildings will make a difference.
Shade during different times of the day will cause temperature differences which can affect growth.
Northern exposures can cause spring thaws a full two weeks later and an earlier frost in the fall. It may be necessary to start some shade plants indoors and be ready to cover plants longer.
The track of the sunlight over the course of the summer.
The amount of water the shade garden receives makes a big difference. Walls, eaves, trees, and slope may make the shade garden a dry garden.
III.Bibliography
Halpin, Anne, Gardening in the Shade, Better Homes and Gardens. 1996
Druse, Ken, The
Schmid, George, The
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