Introduction

• Soil’s physical properties influence plant growth, water movement, aeration, and nutrient retention. These properties depend on soil particle size, shape, arrangement, mineral composition, organic matter, and pore spaces.
• Some of the Key Physical Properties includes:

a. Soil Texture:

• Relative proportion of sand, silt, and clay.
• Affects water retention, drainage, and fertility.
• Loam soil (balanced mix) is ideal for plant growth.

b. Soil Structure:

• Arrangement of soil particles into aggregates.
• Influences porosity, permeability, and root penetration.

c. Consistence:

• Soil’s resistance to deformation when wet, moist, or dry.

d. Adhesion & Cohesion:

• Adhesion: Water molecules stick to soil particles.
• Cohesion: Water molecules stick to each other.

e. Density & Weight Relationship:

• Bulk density: Mass of soil per unit volume.
• Particle density: Density of soil particles only.

f. Soil Color:

• Indicator of organic matter, moisture, and mineral content.
• Dark: high OM; Red/yellow: iron oxides; Gray: poor drainage.

g. Soil Temperature:

• Affects seed germination, root activity, and microbial processes.

h. Water Holding Capacity & Movement:

• Depends on texture, structure, and organic matter.
• Key for irrigation management.

i. Surface Area:

• Finer particles (clay) have larger surface areas, influencing nutrient retention.

j. Soil Porosity:

• Pore spaces for air and water, ideally 50% air and 50% water.