Landscape Designing

LANDSCAPE DESIGNING FRMT 325 Cr. Hr. 3(1+2)

Lesson 13:Landscape Resources: Soil

Chemical composition

• The chemical composition of the soil is important for plant growth.
• The inorganic constituents of the soil are as important to plant growth as its texture and its organic content.
• Sodium, potassium, phosphorous, nitrogen , magnesium, iron and calcium are essential inorganic substances to plants. These have to be replenished by fertilizers.
• A chalky soil is one which contains a high level of calcium.
• It is formed through the breaking down of calcium carbonate (lime stone rock) by the action of the weather.
• Chalky soil contains white particles called caliche and sometimes pieces of flint.
• The top soil is visually thin, allowing water to drain through and warming up quickly in spring.
• It is a very alkaline soil and heavy dressings of organic matter will be needed to counteract the excess lime as well as retain moisture.
• Peat soils are derived almost entirely form plants.
• Peat soils contain less than 50 percent minerals and their high organic content makes them almost black in colour.
• Peat soils are usually wet and badly aerated and extremely acid, but the addition of lime will help to improve both conditions.