How to Create Loam Soil for Your Garden

Loam is soil made with a balance of the three main types of soil: sand, silt, and clay soil. As a general rule, loam soil should consist of equal parts of all three soil types. This combination of soil types creates the perfect soil texture for plant growth.

Loam soil is a combination of three different types of soil—sand, silt, and clay—each with their own characteristics.

• Sand particles are the largest. Sandy soils do not absorb moisture well, but they do provide great aeration, allowing oxygen to reach plant roots.
• Silt particles are medium-sized, absorb moisture better than sand, and help the sand and clay mix together effectively.
• Clay particles are the smallest type of soil particles. Clay-rich soils are known to be somewhat impermeable due to how easily their small clay particles compact together, but clay makes up for its low amount of aeration with a high amount of nutrients.

Loam soil facilitates plant growth in three key ways.

1. 1. Aeration: The varied particle sizes in loam create a loosely-packed soil that allows oxygen to flow freely to plant roots.
2. 2. Nutrient retention: The presence of clay in loam ensures that nutrients cling to the soil, rather than being washed out by water. Loam also creates an ideal habitat for the beneficial microorganisms that help plants flourish.
3. 3. Moisture retention: Water drains through loam at the ideal pace—slow enough for plants to access the moisture, but fast enough to prevent the soil from becoming too soggy.

To see if your garden soil is already loamy is to pick up a fistful of slightly damp soil and squeeze it tightly into a ball. Open your hand and observe the soil: Loamy soil will remain in the shape of a delicate ball but will crumble when you poke it.

If your garden soil doesn't pass the ball test, it has an unbalanced mixture of sand, silt, and clay. Soil that is too heavy on clay may require the addition of sand, but in general, the key to fixing imbalance soil is to blend it with organic matter. Mixing organic material into the soil attracts beneficial organisms that create a higher quality, loamy soil over time. Here's how to add organic matter to your garden soil to make loam:

1. 1. Apply a two-inch layer of organic matter to your topsoil. This should be done in late autumn once your harvest is finished. Common types of organic matter to use include compost, animal manure, green manure, dried leaves, and grass clippings.
2. 2. Wet the layer of organic material until it's fully waterlogged. Let it rest throughout the winter.
3. 3. In spring, work the organic material into the soil to a depth of seven inches. A rototiller can be used to more effectively mix the soil. Repeat the entire process annually for sustained results.

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