Soil texture varies depending on your location, and it can significantly impact the viability of outdoor plants. As such, many gardeners wonder if soil texture can be changed.
It’s possible to change soil texture. The best way to change soil texture is to amend it with alternative soil types. For example, you can change the texture of clay soil by adding significant amounts of humus (decayed organic material), sand, peat, or loamy soil.
This article will discuss the textures of common soils and explore how soil texture impacts plant health. We’ll also reveal how to alter soil texture, helping you amend pre-existing soils to make them suitable for a variety of plants.
The Factors Impacting Soil Texture
Before discussing soil types and their associated textures, we must first define the factors impacting soil texture.
Generally, the organic components that comprise a soil sample are the primary factors that define its texture. These components often include:
Temperature and climate can also impact soil texture. For example, humus-rich soil that’s loose and granular can become hard and gritty when exposed to high temperatures and low-moisture environments. Consequently, natural climate changes can lead to soil texture changes.
That said, the types of soil contained in a particular sample tend to have the most immediate impact on its texture.
Let’s touch on common soil types to understand how their composition affects texture.
Soil Types and Textures
There are several soil types, and each one has a characteristic texture. The most common types of soil found around the planet include:
Clay Soil Texture
Clay soil contains super fine particles. It is sticky and dense, much like the clay you’d use to create pottery. These qualities make clay an excellent building material. However, the clumping, moisture-retaining nature of clay soil can make it a challenging soil for gardens.
Sand Soil Texture
Sandy soil is essentially the opposite of clay soil. This soil is loose, extremely malleable, and drains pretty quickly. It’s also quite gritty. If you ever made sandcastles while playing on the beach as a kid, then you’re most likely familiar with the texture of sandy soil.
Peat Soil Texture
Peat is similar to clay as it has a dense texture that traps moisture. However, peat tends to be more lightweight, mainly when dry. This acidic soil is primarily made of humus, a term used for decayed organic matter (rotten leaves, decayed moss, decomposed sticks).
Silt Soil Texture
Like peat, silt is a nutrient-rich type of soil. However, silt’s texture is more similar to sand because it sports delicate pores that allow water to drain pretty quickly. In fact, dry silt particles feel just like flour. This type of soil typically forms at the bottom of riverbeds and lakes.
Chalk Soil Texture
Chalk is a type of rock that can become a soil-like substance due to erosion. That’s because chalk is far softer than other types of stone and is also highly porous. So, for example, you could crush small chalk rocks (when dry) into a fine powder using only your hands!
Still, chalk soil tends to be a nutrient-poor growing media (much like sand). It’s nearly the antithesis of peat soil, as it’s highly alkaline. This crumbly soil is best used as a soil amendment due to its relative density and lackluster range of nutrients.
Loam Soil Texture
Loamy soil is primarily made of humus, sand, and silt. It’s rich in nutrients, drains at a medium pace, and has plenty of pores to allow for rapid root growth. Most store-bought gardening soil falls into this category.
The texture of this soil varies depending on its moisture content. However, its characteristics include slight clumping (especially when moist) and a granular texture that’s easy to crumble in your hands.
How Soil Texture Impacts Plant Growth
As we have seen, every soil has a distinct texture that differentiates it from other soil types. But did you know that these textures can impact plant growth?
Soil texture primarily impacts plant growth by affecting:
- Soil pore size
- Soil drainage
- Plant root growth
Let’s explore these effects in greater detail to understand why soil texture is essential to maintaining a healthy garden and lawn.
Soil Texture Impacts Pore Size
Soil pores are tiny bubbles of space between particles of soil. These small spaces trap oxygen and water, two substances plants require to flourish.
Soil types known for having a loose texture (like sandy soils) have a much higher number of pores. However, this prevalence of pores can make it challenging for plants that require moist soil to thrive.
Conversely, clumping clay soil may have virtually no pores, especially when wet. This quality makes it a relatively anaerobic environment, offering little oxygen to plant roots. And as you may have guessed, these pore sizes also affect soil drainage.
Soil Texture Impacts Drainage
Not all plants share identical drainage needs. For example, plants native to arid environments (particularly deserts) often prefer dry soils that drain quickly. However, plants native to lush rainforests prefer wet soils that drain slowly.
The texture of any given soil sample determines how quickly it drains. Soils that drain at a medium rate (like loose, loamy soil) tend to be appropriate for most plants. That said, plants with specific drainage requirements may require a different soil texture to experience optimal drainage.
Soil Texture Impacts Root Growth
Another vital aspect of soil texture is root growth. After all, roots require space to extend and spread. Still, soils with dense textures may not allow for much root growth. The densest and stickiest soils (clay and chalk) can be punishing on plant roots, making it challenging for plants to thrive.
Soil texture is also related to soil nutrients, affecting plant growth and viability. For example, soil primarily made of chalk can form small chasms that allow roots to grow, but it’s typically void of life-sustaining nutrients. In contrast, sticky clay soil is often rich in nutrients but can be incredibly dense and water-rich, resulting in root rot.
Fortunately, gardeners can change soil texture by following a few simple steps.
How To Amend Soil Texture
If you’re looking to change the texture of your soil, you’ll need to amend it using an alternative soil type. To do this, you’ll most likely want to:
- Consider the current texture.
- Research your plant’s preferred soil drainage level.
- Choose an appropriate amendment material.
- Mix the amendment material with the pre-existing soil.
Let’s explore these steps in greater detail to ensure you enjoy a successful texture change appropriate for the plants you’d like to grow.
Consider Current Texture
The first thing you’ll need to do is determine what type of soil you’re currently working with. You’re likely dealing with loam soil if you’ve purchased garden soil from a local plant nursery or home improvement store.
However, if you’re working with native soil, determining its type can be more challenging. Still, you can refer to the soil types and textures listed above to help determine the native soil type. Remember, clumping and drainage are two of the most significant indicators.
Research Your Plant’s Preferred Soil Drainage Level
After you’ve figured out what kind of soil you’re working with, it’s time to take a moment to research your plant’s preferred soil type and drainage level.
For example, if you’d like to grow petunias in native soil, you’ll want to ensure the soil is a mix of sand and loam. However, if you’re looking to grow tomatoes, you’ll want to use well-draining loamy soil with smaller quantities of sand and silt.
Choose an Appropriate Amendment Material
After you’ve discovered what soil your plant prefers (sand, clay, loam), you can now choose an appropriate amendment material. Naturally, it’s crucial to select an amendment that allows you to transform the pre-existing soil into the ideal soil type for your plants.
So, if you’d like to create a cactus-friendly garden in your backyard, but the native soil is primarily clay, silt, or loam, you’ll want to choose sand as your primary amendment material.
Alternatively, if you’re hoping to grow a vegetable garden in an area with sandy soil, you’ll need to amend the pre-existing soil with loam and silt soils.
Mix the Amendment Material With the Pre-Existing Soil
After you’ve chosen a suitable amendment material, it’s time to incorporate it into the pre-existing soil. Naturally, the right amount of amendment for your soil depends on the amount of soil you’re looking to amend.
For example, if you’re creating raised garden beds in an outdoor space, you’ll want to measure the space before purchasing amendment materials. You can use a soil calculator to determine the amount of soil you’ll need to fill that bed.
After that, it’s simply a matter of calculating the desired ratio of pre-existing soil and amendment material and filling the space. Thus, if you’re looking to create a loamy soil for such a garden bed, and you’re starting with clay soil, you’ll need to mix in a significant amount of silt and sand (resulting in 80% to 90% sand and silt).
Nonetheless, of course, if you’d like to minimize the math required to change soil texture, you can’t go wrong with adding store-bought garden soil and organic manure. Both substances are ideal for most types of plants.
The primary exception to this rule would be gardens featuring plants that prefer sandy soils, like cacti and succulents. In this instance, it’s best to amend the soil with sand, chalk, and small rocks.
There are several soil types, and each has a unique texture. Loamy soil is the most common type used in gardening. This soil has a loose texture and plenty of pores, ensuring plant roots have access to water and oxygen. Loam soil also offers better drainage than clay or peat soil.
Soil texture affects drainage, pore size, and root growth. For these reasons, you may want to change soil texture by amending it with other types of soils or natural materials. However, you’ll want to consider your soil’s current texture and your plant’s drainage needs before altering it.
If you want to learn more about improving soil quality, you can read my other article here: How To Improve Soil Quality (The Ultimate Guide)