6 Soil Types: How to Prepare Different Soil Types for Gardening

Soil is the top layer of the land surface of the earth known as the pedosphere. It is made up of organic matter, minerals, gasses, liquids, and living organisms. All of these components work together to support animal and plant life on earth. Soil provides a medium for plant growth, water storage, and habitat for various life forms. Soil is one of the earth's most vital natural resources. Soil science is the study of soil and the various environmental factors impacting soil quality. Soil scientists continue to discover ways in which land use and pollution contribute to climate change, soil erosion, and soil degradation.

Soil types can be categorized by the size of soil particles. Consider some of the most common types of soil.

1. 1. Clay soil: Clay soils are dense, high in nutrients, and contain more than twenty-five percent clay particles. Clay soil particles are small and tightly packed together with very little airspace between particles. They retain a high amount of water but offer poor drainage. The size of the particles makes it difficult for plant roots to take hold and can prove to be a challenging soil profile for gardeners. Depending on the clay content, clay soils may be considered clay loam or sandy clay.
2. 2. Sandy soil: Sandy soils contain a high concentration of rock particles. They are light, warm, and airy soils that tend to have an acidic pH level. They are free-draining soils that offer very little in the way of nutrients and water retention, which can hinder plant growth. The addition of organic matter can improve the soil structure, providing plant roots with more nutrients and a sufficient amount of water.
3. 3. Peat soil: Peat soils are high in organic material. They are high in nutrients and provide very good drainage. Peat soils are typically added to existing topsoil to amend the soil structure and provide nutrients for plant growth.
4. 4. Silt soil: Silty soils have good aeration and a high fertility rating. Silt particles are smaller than sand particles but larger than clay particles. They retain a high amount of moisture but can be easily washed away by heavy rains or currents.
5. 5. Loam soil: Loamy soils contain a mix of clay, sand, silt, and humus. Depending on the ratio of the different soil types that make up loam soil, it may be considered clay-loam, loamy sand, etc. Loamy soils are high in nutrients, have good water retention, and have good drainage. It is one of the best agricultural soils and is ideal for use in a raised garden bed.
6. 6. Chalky soil: Chalky soils contain a high amount of calcium carbonate, making them high-alkaline soils. Chalky soil has a fine soil texture that dries out easily. Plants that require acidic soil will not survive in chalky soil. In some cases, chalky soil can be acidified but more often than not, gardeners are better off only using plants that tolerate alkaline soils.

Before planting in your garden, make sure you've got good soil first. Consider these tips for improving any type of soil.

1. 1. Clear away rocks. An abundance of rocks in the soil is a likely indicator of poor soil quality. They provide little to no nutritional value and make landscaping difficult. Rake the topsoil to remove surface rocks. Applying a six-inch layer of organic matter, such as mulch and grass clippings, can help provide enough organic soil for plant roots to grow. If your garden beds are full of large slabs of rock, consider using container plants or planting in raised beds instead.
2. 2. Aerate your soil. Aerating your soil has a number of benefits for your plant, from improving water drainage to increasing proper nutrient uptake. There are different methods of aerating soil, including spiking the soil, removing “plugs” of soil from the ground, or using liquid aeration.
3. 3. Check and adjust the soil pH. To determine the soil pH, perform a soil test. The optimal pH range for most food plants is slightly acidic, from 5.5 to 6.5, so if the pH of your soil falls outside of this range, you may need to apply soil amendments to get your garden ready for plants. Certain plants will thrive in slightly different conditions. For instance, pineapples, blueberries, azaleas, and rhododendrons are known as “acid-loving plants” because they thrive in more acidic soils (between 4.0 and 6.0). Plants like asparagus, honeysuckle, and lavender can handle more alkaline conditions (between 6.0 and 8.0). Add ground limestone or wood ash to your existing soil to raise your soil pH. To lower your soil pH, consider applying organic fertilizer, compost, or sulfur compounds.
4. 4. Condition the soil. Soil conditioning is the process of improving poor soil to promote the growth of healthy plants. Soil is mostly made up of clay, sand, and silt. The percentage of these and other components will affect the soil texture, which determines its water holding capacity and aeration levels. A soil structure is loamy—or healthy and fertile—if it has an optimal clay, sand, and silt balance. If not, you can add various soil conditioners such as microbes and peat moss to improve soil quality. This will also help with water retention.

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