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

Growing Media When growing plants in a greenhouse, dirt from the ground cannot be used because it may contain: Insects Diseases Weeds Greenhouse plant growers will mix different soil-less materials together to make a soil suitable for growing plants inside of a greenhouse in containers.

Organic Soil-less Media Components Media is any matter, excluding organic soil, used for the production of horticultural plants. Soil-less media does not contain natural soil. The soil is replaced by other materials

Organic Matter (OM) Dead plant or animal tissue contains carbon usually has diseases or insects

Types of Organic Soil-less Media Peat Moss Organic and has a slightly acidic pH Partially decomposed material mined from the swamps Has good moisture holding properties

Types of Organic Soil-less Media Compost Decayed organic matter Compost is used for soil conditioning and fertilizer.

Types of Organic Soil-less Media Sphagnum Moss Sphagnum is organic and is very acidic Dehydrated remains of acid bog plants Holds moisture Commonly used line wire hanging baskets

Types of Organic Soil-less Media Bark Organic and slightly acid pH Larger matter added to some horticulture media to promote drainage Adding bark to a soilless mix usually makes the mix heavier Widely used in tree and shrub production

Additional Organic Materials Used in Soil-less Media Mixes Sawdust and Wood Shavings Have a high carbon to nitrogen ration Make nitrogen unavailable for plant use Organic materials must be well rotted or decomposed to avoid problems with nitrogen tie-up.

Inorganic compounds Do not contain carbon usually sterile

Types of Inorganic Soil-less Media Vermiculite A light-weight mica mineral matter commonly used to start seed and cuttings. Inorganic and has a slightly alkaline pH Holds moisture

Types of Inorganic Soil-less Media Perlite A natural volcanic material Slightly alkaline pH Helps with soil aeration and drainage

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

Soil Profiles and Sampling

Objective 5.02 Discuss the soil profile and soil sampling for surface and subsurface layers

Soil Profile Soil layers are called horizons All soil profiles do not have the same number of horizons Most typical soils in NC will have a minimum of the A, B, and C or R horizons.

Soil Profile O Horizon A Horizon Rich Soil found where a plant cover has been in place for an extended time Is rich in Organic Matter. Dark in Color Most fertile layer in the soil The topsoil and most fertile in the absence of an O Horizon Home to earthworms and soil organisms Brown in color

B Horizon Subsoil Clayey soil with high mineral content Brown to Reddish in Color C Horizon Parent Material Mostly Clumps of un- weathered rocks R Horizon Bedrock Very few roots can penetrate

Soil Structure How particles cluster together single grain granular (best for most plants) blocky platy 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 Granular soil structure is the best. Plants have good root development Water movement is at an appropriate rate

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

Silt Medium sized particles Good moisture and nutrient holding capacity

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 Neutral - 7 Most organic matter is acid Most artificial media is neutral Ideal pH for most gardens is 5.5 to 7.0 Lime will raise the pH value in soils Calcium or sulfur will lower the pH Value

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 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