Shade Garden Ideas

The incorporation of quantities of organic matter into the soil results in the superior growth of plants for several reasons, the most important of which is the effect organic matter has on soil structure. The word structure, as it applies to soil structure. The word structure, as it applies to soil, refers to the way the particles of soil stick together. Soil with good structure has the right amount of air space to promote both good drainage and adequate water retention. And good drainage is particularly important in shaded garden locations. Because of the absence of direct, intense sunlight, shaded soil tends to stay damp much longer than it would in sunny location. Without excellent drainage, the gardener is likely to experience water-related growing problems such as stunted, weak plants and the presence of fungus diseases.

How can you tell if your soil has good structure? The following characteristics are good indications:

• The soil doesn’t compact down after a watering or rain, and doesn’t leave a hard crust on the surface as it dries.
• The soil is easy to work using a hand spade or cultivating fork.
• The soil is friable—it has a loose, almost “fluffy” texture.

Plants vary greatly in their requirements for air in the soil. But in looking at the air requirements of some favorite shade plants, it becomes obvious that the addition of organic matter is doubly important in shade gardening. The aeration requirement of plants is measured by the percentage of air space left in the soil after excess water from irrigation has drained away. Azaleas and most ferns have a requirement of 20 percent or more, which is considered very high. To get this level of aeration, many commercial growers grow azaleas in unmixed, coarse peat moss. Rhododendrons, begonias, and many foliage plants have air requirements of 10 to 20 percent, which is still high. Even plants classified as tolerant of low levels of aeration, such as ivy, will grow better with high percentages of air in the soil.