Clay, silt or sand – the texture of your soil will define your garden. If you've discovered a patch of soil that looks like a great place for a new garden, the first thing you need to do is define your soil. Once you know the natural state of your soil, you can manipulate the layers to nurture healthy lush foliage. (However, you might also learn that a rock fountain or freestanding deck is better suited for the area.)
Soil texture is categorized in three familiar terms: clay, silt and sand. These categories are based on the size of the soil particles. The soil you are considering for your garden will be a mix of these particles. Sand is the largest type of particle, and ranges from a “massive” .002 to .08 inches in diameter. Silt is a soil particle that measures between .00008 and .002 inches in diameter – somewhere in the middle of sand and clay. Clay is actually the smallest. A soil particle that is smaller than .00008 is categorized as clay. A soil with clay, silt, sand and organic material is referred to as loam. Your garden soil can be defined by what type of like particles are combined together. Ideally (although there's always exceptions), you want your soil to be 40% silt, 40% sand,15% clay, and 5% organic content.
Sand granules are large and loose. Water drains through too quickly, but there is room for roots to grow. Clay granules are small and tight. Clay holds water, but water and roots get trapped. However, clay does very well at trapping beneficial nutrients. The absorption and flow of water is tempered between the two extremes with silt.
You don't have to get out a magnifying glass to separate, count and measure every minuscule grain to determine the mix of your soil. A garden shovel, a pail, a glass jar with a lid, and a little patience can do the job.
Look at the area you're considering for your new garden. Within that area, get a few garden shovelfuls of soil that are representative of each part of your garden. Mix them all together in a pail and shake it up real good. Then get a good-sized glass jar (coffee-pot size would be practical), and put soil from the pail into the glass jar until it's about 1/3 to 1/2 full. Then fill the rest of the jar up with water. Cover the jar and shake up the soil and water until all the particles are floating around in the water.
Next is the hard part – let the jar sit until all the particles settle. This could take a couple days, particularly if you have a high percentage of clay in your soil. But you will see some soil settling in a couple hours. Sand drops to the bottom first because it has the larger particles. Next will come silt, then clay. Any organic material will just float around or eventually settle on top of the clay. Getting an accurate picture of your soil composition will help you get the best garden for your gardening, so don't rush the process. (Keep in mind that leaving the jar where kids will have fun shaking it up might delay the process.)
Once the soil in your test jar has settled into layers, you'll have an idea of what percentages you're working with and what amends you'll need to make for a healthy, lush garden. Knowing your soil composition will also save you from buying seedlings that aren't likely to thrive.
Playing in the soil is half the fun of gardening. But before you select your seedings, give a little shake to your soil. Once your soil is situated, you can be sure that you'll plant a garden that will firmly take root – and you can just sit back and watch it grow.