Depending on how long you’ve been in the gardening game, you may have already heard that “loam” soil is an ideal growing medium for most plants. That’s good news, but what does “loamy” soil actually mean?
Soil is generally classified by its texture; either sandy, silty or clay-like. Each soil type possesses certain qualities depending on the size of its particles. As a general rule of thumb, loam is an equal ratio of sand, silt, and clay soils. However, you may require slightly more sand or clay in your garden depending on the climate you live in.
The Qualities of Loam Soil
Loam is generally an equal mix of sand, silt, and clay soils. These soils all contain different-sized particles that determine their texture.
Sand particles are the largest; creating space while being unable to retain water.
In contrast, clay particles are fine and easily compacted. The clay in loam soil promotes water retention while providing little space between its small particles.
Silt particles are somewhere in between in size. They are necessary to hold the sand and clay particles together.
Loam soil is friable, meaning it has a loose, crumbly texture. The proper ratio of sand, silt, and clay particles in loam produces mouldable, but not sticky soil.
It is loam soil’s balanced composition and proficient texture that makes it an extremely efficient, fertile growing medium.
Benefits of Loam Soil
1. Drought Resistant
Loam soil retains enough water for plant roots to sip before it is proficiently drained. Clay particles in loam soil compact easily making them great at retaining water. Loamy soil is, therefore, less susceptible to drought.
2. Promotes Water Drainage
While the clay particles aid in drought prevention, the sand particle content of loam soil is responsible for its ideal drainage properties. Having the largest particles, sand provides space for water to move throughout the soil. This is crucial in a growing medium to prevent root rot from occurring.
3. Enables Aeration
Similarly, the space created by large sand particles in loam soil is responsible for its productive aeration. It is this space that enables plant roots to be oxygenated while preventing soil compaction.
4. Promotes Root Health
On top of providing oxygen, the friable texture of loam soil enables water as well as nutrients to reach plant roots. It also promotes the formation of strong and deep root systems which are vital for plant longevity.
5. Provides Nutrients
The nutrients found in loam soil are a product of its negatively-charged clay particles. These particles attract positively charged nutrients in your soil, such as calcium, iron, potassium, phosphorus, and magnesium. This mineral content nourishes your plants, helping them grow big and strong!
6. Aids Beneficial Organisms
Worms and micro-organisms thrive in loam soil due to its ideal texture. They are able to move about freely between the particles, decomposing organic matter and distributing nutrients throughout your garden bed. Promoting the natural ecosystem in your garden is key to plant success!
How do you know if you have loam soil?
The simplest way to determine if you have loamy soil is by rolling it into a ball. If the ball is too loose and crumbles away, you’re looking at sandy soil. Alternatively, if you end up with a hard, dense sphere you likely have clay soil.
The best way to determine your soil composition is with a soil test. You can send in a sample, or use a DIY soil test at home. A soil test provides information on your soil’s texture and composition, as well as any nutritional deficiencies you might be looking at.
How to Create Loam Soil
Unfortunately, fixing your soil is never as simple as adding one type to another. For example, it may seem natural to add sand to a heavy-clay soil; however, this mix results in a substance more similar to concrete than loam.
Therefore, it is best to use the information provided on a soil test and add the appropriate amendments to your soil. Amendments usually include a form of organic matter such as compost, which is dug into your existing soil.
This organic matter adds humus to your soil as it decomposes. Humus acts like a glue to hold particles together and improve the structure of sandy soil. In clay soil, dug in organic matter creates the space between particles that is necessary for aeration and water drainage.
Alternatively, to dig organic matter into your garden, try the no-dig gardening method to create healthy loam soil consistently over time.
How to Sustain Loam Soil
Consistently adding organic matter throughout the season is the best way to create and sustain loam soil. It will give your soil a nutrient pick-me-up while improving the texture and overall quality.
Try implementing the no-till gardening method to fix the soil in your backyard! Over-tilling releases precious nitrogen that is stored within the soil. Additionally, it disrupts the habitat of beneficial micro-organisms.
Plant a Cover Crop
Keep your soil fertile and aerated by planting a cover crop between growing seasons. This will aid with soil erosion and replenish soil nutrients.
Try not to walk on your soil unnecessarily, especially when it is wet. Avoiding compaction whenever possible enables your soil to retain a healthy structure.
Test Soil Annually
Test your soil annually by sending in a sample or using a DIY soil test. This is the best way to keep on top of your soil’s health and figure out what amendments it may need to become loamy.
Loam soil is a balanced ratio of the three main types of soil; sand, silt and clay. This fertile mix boasts the positive properties of each soil type and doesn’t bother with the negative. The resulting combination is a fertile growing medium that is suited to most plants. Test your soil to determine whether it may be too sandy, silty, or clay-like. Add the appropriate amendments to transform your backyard soil into loam!