The Difference Between Garden Soil and Raised Bed Soil

Soil, the top layer of the earth’s surface, is essential to supporting life. It contains a myriad of living organisms as well as decaying matter. Top soil refers to the uppermost layer of soil on the earth. For those seeking to plant a garden, knowing the difference between garden soil and raised bed soil is crucial. Many gardeners disregard the differences, which is a gardening mistake that can result in suboptimal produce. One such difference is the amount of heat and moisture that each requires for breaking down the organic material, a second is the amount of humus present in these soils. 

Humus is the dark organic material in soils produced by the decomposition of plant or animal matter. The greater the quantity of humus in the soil, the more effective it becomes for your vegetables and plants. Garden soil ends up breaking down more quickly than can be restored by gardening. Soils with high moisture content also have less longevity. The article below will examine the differences between raised bed soil and garden soil, their various applications, and will help you determine the best soil for raised garden beds.  

Which is the Best Soil for Raised Garden Beds?

Garden Soil:

Garden soil is soil that contains topsoil as well as forested products, which is essentially wood. It is not designed for raised beds or containers because it over-compacts and has a tendency to become oversaturated with moisture, leaving limited space for roots to grow. Compared to potting soil, it has a heavier texture and increased water retention. 

To clarify, potting soil, also called potting mix, is not actually soil. It is a man-made material composed of natural substances, including decomposing bark, peat moss, minerals, and perlite. It is ideal for growing plants in small containers or pots. The main difference between garden soil and potting soil is the addition of topsoil, which makes garden soil heavier. Garden soil also lacks ingredients such as perlite and peat, making it less expensive than potting mix. 

Due to the high moisture content, garden soil can contain a comparatively high volume of salts, making it extremely corrosive. If the soil is left in a covered driveway for an extended period of time, then it can cause damage to the driveway. To ensure soil durability, you should dig a shallow hole approximately 6 inches deep, and then spread the soil in your garden bed. Doing so will allow the salts present to seep into the soil properly. 

Garden soil is ideal for in-ground gardening, as it contains many benefits like reducing native soil compaction, and improving soil composition. Garden soil contains essential nutrients that can aid native soils in nutrient retention and help promote stronger root systems. When compost-rich garden soil is added to native soil, the quality and structure of the native soil is improved due to the lessened compaction. Even soil that is deficient in nutrients can be revitalized by adding garden soil. This is because garden soil contains a good mixture of contents that make it well-draining and fluffy, ideal for supporting moisture retention.

Despite its benefits, the particle size of garden soil is too dense to be used in containers or raised garden beds. Although nutrient rich, the moisture retention is inadequate to support plants and vegetables grown in a raised bed.

Raised Bed Soil:

The ideal soil type is sandy loam, which is essentially soil that is loose, well-draining, and rich in organic matter. Oftentimes the native soil in your yard is not suitable for growing plants, as it may have poor drainage or subpar composition. It may also contain heavy metals or pesticides. 

It is a best soil for raised garden beds formulated with an ideal balance between potting soil and garden soil. Potting mix is too light to be raised in beds, while garden soil is too heavy. Raised bed soil possesses amazing drainage properties that help establish a favorable environment for your plants. It provides gardeners with well-maintained loose soil that results in adequate airflow and distributes a sufficient amount of nutrients and oxygen to the root systems of plants. You can use raised garden bed soil for both metals raised garden beds and galvanized raised garden beds. 

It is best soil for raised beds where the plants soils do not need to be constantly watered and maintained due to the exceptional. They are also less likely to be affected by pests or disease. Although raised bed soil is more expensive than lesser quality soils, it is best to invest in it as soil is one of the most important factors that determine the success of a garden. Using poor quality soil can have detrimental effects on root growth, which in turn leads to a shortage of vegetables. 

Add in fertilizer: The best soil for raised beds contains nutrients that promote growth. Raised bed soil is nutrient rich and contains a higher percentage of organic material than garden soil. However, you should also add additional organic fertilizer throughout the growing season to ensure a productive harvest. Organic and natural fertilizers include compost, algae and worms. These fertilizers can improve the quality and condition of the soil without concerns about pollution. 

The best soil for raised garden beds also has an ideal pH balance between 5.8 – 7.5, which is optimal for your vegetable or flower garden. As well as regulating pH levels, raised garden soil also helps plants maintain higher nutrient levels. Although raised garden bed soil is formulated as ready to use from the bag, many gardeners still choose to add compost or soil amendments to fortify the soil. The fun part is experimenting to see which types of vegetables thrive in which types of soil! 

Using soil amendments: You can amend the soil if you are not receiving optimal results. For example, if your soil is experiencing drainage problems, add perlite. Some common soil amendments include perlite, vermiculite, sand, and bark. Perlite increases soil aeration and promotes drainage. Vermiculite, a hydrous phyllosilicate mineral, increases soil aeration as well, but also facilitates water retention. By contrast, sand reduces water retention, which you can add if you want to grow cacti or succulents, which thrive in sandier soils. Bark is a primary component of orchid mix, which helps you maintain the right amount of moisture for orchids. Organic mulches will also help with water drainage.

Add to existing soil: Each season, you may find that the soil in your raised garden beds seems to shrink. This can be attributed to beneficial soil microbes that consume the soil and subsequently create beneficial nutrients for your plants to absorb. To replenish the depleted soil, simply spread a layer of raised bed soil leaving 3 – 4 inches of space at the top of your raised bed. During this time, it is a good idea to add in organic fertilizer as well.

Alternative Methods:

You can create your own raised garden bed soil by combining garden soil with potting soil, keeping in mind to use more garden soil than potting mix, usually at a 5:1 ratio. If you want to save money, we suggest you try the Hugelkultur method. Hugelkultur is the method of layering mounds of rotting wood and organic material to replicate an ideal natural environment for your crops. You can easily repurpose existing organic matter on your property, such as wood logs, grass clippings, and branches. Alternatively, you can try a soil blend of 50% topsoil, 30% compost, and 20% organic matter. When buying in bulk, you should try to purchase certified organic compost, as it ensures better quality. Ultimately, the best approach depends on your time, budget, and location.

So - what soil should I use?

Although there are many strong options, one top-contender among the raise garden bed community is Miracle Go Potting Mix. This mix is made with a blend of ingredients that provide the nutrients your plants need to thrive. It contains a variety of materials including coir, compost, peat, perlite, fertilizer and wetting agents.

The compost content has a variety of sources that may include animal manures, composted leaves, grass clippings or composted bark, which provides an equally varied nutrient base that can nourish an assortment of plants. The diversity and inclusion of perlite prevents compaction while improving drainage and aeration. Once applied over quality topsoil, this Miracle-Gro garden soil mix has the nutrients to support plants for up to 6 months.