Click above to view a discussion on how soils hold water at the University of Nebraska site.
Click above to view a horticultural summary of soil properties at the Texas A & M site.
Virginia Extension has information on essential elements, nutrient deficiencies, fertilizers and pH. Click above to view the Texas A & M site for an excellent discussion on plant nutrients. View the "Gardeners Guide for Soil and Nutrient Management in Growing Vegetables" from Nebraska Extension. Look at the North Carolina Cooperative web site and search "fertilizer" for additional soil and fertilizer related topics.
Organic Matter and Humus
Good information on composting from the University of Nebraska website.