Well‑managed soil produces higher yields with better flavor and nutrient density.

Soil Properties

You can categorize soil properties into 3 categories: Physical, Chemical, and Biological.

Physical

1. Water-holding capacity – based on texture of soil, important for balance between water availability and drainage
2. Structure – soil binds together but has sufficient porosity to allow air to pass through

Chemical

1. pH – Determines which nutrients are soluble (lime raises pH, sulfur lowers it)
2. CEC (cation-exchange capacity) – The ability to hold and exchange nutrient ions—higher CEC means better nutrient buffering. CEC specifically measures a medium’s ability to chemically bind and exchange nutrient ions (like Ca²⁺, Mg²⁺, K⁺, NH₄⁺) on negative charge sites. It’s fundamentally about ion chemistry—how many “parking spots” there are for positively charged nutrients, and how readily they swap in and out of solution for plant roots.
3. Nutrient profile – the chemical concentrations of essential elements (N, P, K, and micronutrients) immediately accessible

Biological

1. Organic matter content – amount of decayed plant or animal material in the soil. OM improves structure, water‑holding, and provides a habitat for microbes. Over time, microbes break down OM and slowly release more nutrients.
2. Microbial support – how well the medium fosters a diverse, active community of bacteria, fungi, and other soil life, which improves root health, disease resistance and nutrient cycling

Amendments

Some amendments can improve multiple properties.

Sustainability – peat, cost is superhigh, explain why

More information

Structure

Binding agents glue individual sand/silt/clay particles into clumps (“aggregates”).

• Compost: Full of decomposed organic matter and microbial “glues” that bind particles.

• Biochar: Tiny, porous charcoal pieces with charged surfaces that attract and hold soil particles.

• Humus (leaf peat): Highly decomposed organic matter, rich in humic acids that act like natural adhesives.
• fungal hyphae
• root exudates

Physical agents act as spacers creating tunnels and fissures through those aggregates which keep them from packing too tightly, so air can flow freely and roots can push through.

• Perlite: Lightweight, irregularly shaped mineral bits that refuse to crush under weight.
• Rice hulls: Hollow plant remains that nestle between aggregates and maintain voids.
• Pine bark fines: Chunky fragments that physically prop aggregates apart.
• Earthworms: the best! their castings also act as binding agents, and support microbial life!
• freeze-thaw and wet-dry cycles: also act to shift particles

Test structure by squeezing a handful:

• Should stay in a loose crumb (stability)
• And let air pass through (porosity)—if it cakes or feels gummy, structure is failing.