Soils are generally described according to the predominant type of soil particle present – sand, silt, or clay. By conducting a simple soil test, you can easily identify your soil type. You may want to repeat this test with several different soil samples from your lawn and garden.
- Fill a quart jar about 1/3 full with topsoil and add water until the jar is almost full.
- Screw on the lid and shake the mixture vigorously, until all the clumps of soil have dissolved.
- Now set the jar on a windowsill and watch as the larger particles begin to sink to the bottom.
- In a minute or two the sand portion of the soil will have settled to the bottom of the jar (see illustration). Mark the level of sand on the side of the jar.
- Leave the jar undisturbed for several hours. The finer silt particles will gradually settle onto the sand. You will find the layers are slightly different colors, indicating various types of particles.
- Leave the jar overnight. The next layer above the silt will be clay. Mark the thickness of that layer. On top of the clay will be a thin layer of organic matter. Some of this organic matter may still be floating in the water. In fact, the jar should be murky and full of floating organic sediments. If not, you probably need to add organic matter to improve the soil’s fertility and structure.
Stay tuned for our next blog post, where we’ll discuss how to manage sandy, silty and clay soils and the ideal plants to grow in each soil type. In the meantime, try the jar trick and tell us what type of soil you’re working with and how you’re managing that soil.
The Ideal Soil Type: Loam
The type of soil plants and gardeners love is a loamy soil. Loam soil holds a balance of all three soil materials—silt, sand and clay—plus humus. Loam has higher pH and calcium levels because of its organic matter content.
Loam is usually darker in color and is mealy—soft, dry and crumbly—in your hands. It has a tight hold on water and plant food but it drains well, and air moves freely between soil particles down to the roots.
To describe loam in words… hmmm how do you describe how something feels… ? It can be smoother than pure compost. Loam will be gritty, if it is moist it will form a sticky ball in your hand that will crumble easily.
Although loamy soil is the ideal material to work with, don’t freak if you don’t have perfectly loam garden soil. That’s because soil will always favor one particles size over the two others. Then again, there are many ways to condition your soil—adding beneficial soil innoculants, covering your soil with compost, or simply spraying leaves and soil with compost tea.