Soil Properties Essential Standard 5.00- Explain the role of nutrients and fertilizers.
Objective 5.01 Discuss Horticulture soils
Soils and growing media Soils and growing media are made up of two types of materials Organic matter Inorganic compounds
Organic Matter Dead plant or animal tissue contains carbon usually has diseases or insects
Types of organic matter Compost bark-particles too large to use in seed germination media mulch-used to cover soil to help hold moisture and prevent weeds straw peat moss
Composting
Types of Organic Matter Sphagnum Sawdust-high carbon to nitrogen ratio makes nitrogen unavailable for plant use Wood shavings- high carbon to nitrogen ratio makes nitrogen unavailable for plant use
Inorganic compounds Do not contain carbon usually sterile
Types of inorganic compounds Soilless media-artificial soil Vermiculite-mica mineral matter used to start seeds and cuttings, helps hold moisture, has neutral pH Perlite-natural volcanic material that helps aeration and water-holding capacity
Vermiculite
Perlite
Advantages of horticultural soils Sterile. pH is neutral. Disease and weed free. It is good for starting disease sensitive seeds Tomato It is easy to control the nutrient content Improves crop uniformity. It is easy to create a horticulture soil for particular plant needs.
Disadvantages Expensive It is light weight
Carbon : Nitrogen Materials with a high carbon to nitrogen ratio Sawdust Wood shavings Makes nitrogen unavailable for plant use
Soil Profiles and Sampling
Objective 5.02 Discuss the soil profile and soil sampling for surface and subsurface layers
What is the physical make up of soil?
Soil Profile Layers of soil are called horizons Typical profile A Horizon-topsoil most fertile most organic matter top or first layer B Horizon-subsoil C Horizon-bedrock
Soil Profile A Horizon B Horizon C Horizon
Soil Profile
Soil Structure How particles cluster together single grain granular (best for most plants) blocky platy massive
Soil Structure Single Grain
Soil Structure Granular
Soil Structure Blocky
Soil Structure Platy
Soil Structure Massive
Soil Structure Soil structure is more important to producers who grow plants in natural soils Producers of container grown plants add ingredients to make growing media desirable
Soil Texture Size of particles Types of textures clayey loamy sandy
Clayey Texture Small particles Has a high water-holding capacity most common texture in western NC
Loamy texture About equal parts of sand, clay and silt Ideal texture for most non-container outside plants
Sandy texture Large particles Low moisture-holding capacity Most common in eastern NC
Soil pH Measurement of acidity or alkalinity from 0 to 14 Acid-less than 0-6.9 Alkaline-more than 8-14 Most organic matter is acid Most artificial media is neutral Ideal pH for most gardens is 5.5 to 7.0
Physical Properties of Soils Permeability rate at which water moves through the soil Water holding capacity ability of a soil to hold water for plant use Porosity amount of air space between soil particles
Physical Properties of Soils 50% of soil should be pore space 25% water space 25% air space. 50% of soil should be soil particles 45% mineral matter 5% organic matter
Soil Makeup Water
Soil Sampling Soil sampling and testing is essential for an accurate fertilizer recommendation for growing plants.
Soil Sampling Procedures Create a visual grid of the area to be planted. For gardens and landscapes, take 5-10 sub-samples Sample before the growing season. Use a stainless steel soil-sampling probe. Take the surface sample to tillage depth about 4inches for lawns 6-8 inches for crops Mix the soil samples together.
Soil Sampling Procedures Remove any grass, rocks or other material besides soil. Avoid unusual spots Problem areas need to be sent in a separate box. Place soil samples in a box Obtain from the County Extension Office along with Soil Sample Information sheet Send the box and information to: Agronomic Division Soil Test Lab in Raleigh for a free soil test.
FFA Land Judging CDE