Testing Your Soil Composition

Soil composition is another factor that plays an important role that determines how well your plant can survive being planted in your soil other than soil fertility. Soil composition refers to the texture of the soil, as well as the organic matter that it has.


The texture depends on the particle size of the soil. There are two extreme types of soil: sandy soils with very large particles where water, air and plant roots can move easily BUT has trouble retaining nutrients and moisture; and clay soil which is nutrient rich, is packed together BUT leave very little room for water, air or roots to move about. The trick of the trade is to obtain a balance between both, getting what is called a sandy loam type of soil that has some characteristics of sandy soil that is light, will allow water and air movement but have some tilth and is nutrient rich like clay soil. It should have a fine bread crumb like texture, which denotes an organic matter rich soil.

The Squeeze Test

Knowing the type of soil you have will be a good starting point for you to make amendments to it before planting. This is an easy way to determine the type of soil you have in your garden:

  • Grab a handful of moist (but not wet) soil from your garden, and try to shape it into a ball by giving it a firm squeeze.
  • Open your hand. If the soil holds its shape, and crumbles when you poke it, you have loam soil. If it holds its shape, and doesn\’t crumble when you give it a poke, you have clay soil. If the soil falls apart as soon as your hand opens, you have sandy soil.

The Percolation Test

Drainage capabilities of your soil are also a factor that you must pre-determine before you start your planting project. If your soil does not drain well, you may end up with root rot because of water clogging and destroying your plants roots. Plants like culinary herbs will die if the roots stay too wet. Here\’s a simple way to test your soil\’s drainage:

  • Dig a six inch wide by one foot deep hole in the area you want to test.
  • Fill the hole with water
  • Allow it to drain completely.
  • Fill it with water again, then time how long it takes for the water to drain again.
  • If it takes more than four hours to drain, then you have soil with poor drainage. You will need to take steps to amend this.

Organic Matter

Organic matter, like soil pH, is important to ensure a healthy plant growth. Organic matter is made of dead plant or animal material. It is always present in the soil, but whether it is in a sufficient amount that will support the plant\’s need is another matter altogether. Decaying organic matter, or humus, also provides your soil with some tilth, and helps sandy soil retain water. It also corrects clay soil by making it less compact, allowing air, water and roots to penetrate to the soil.

The Worm Test

Mother Nature is half the time the best indicator of the overall health of your soil. Worms will show if your garden soil is healthy in terms of biological activity. The presence of earthworms indicate that there are plenty of beneficial microbes and bacteria in your soil, which in turn will ensure that your plants will attain optimal amounts of nutrients required for healthy growth. Here\’s how you do a worm test:

  • When the soil is about 55 degrees, and is moist (not soaking wet), dig a hole about 1 foot by 1 foot.
  • Place the soil that you\’ve just dug up on a tarp or piece of cardboard.
  • Count the number of earthworms in the soil sample you have just obtained as you sift through, returning the soil (and the earthworms back into the hole of course).
  • If you have at least ten worms, it is an indication that your soil is healthy. Any less than 10 usually denotes a lack of organic matter in the soil to support a healthy worm population. It can also be an indication that your soil is too acidic or alkaline.

Amending texture and organic matter

Once you\’ve done your soil test for texture and organic matter, take the required steps to amend them as required. You can amend the texture and increase the amount of organic matter in your soil by adding:

  • Compost which can be made by yourself with garden and kitchen waste (refer to making compost chapter)
  • Manure which must be composted and decomposed until it turns into a dark, crumbly and odorless material. Do not use fresh manure as it has too much ammonia and can burn your plants (as well as offending your neighbors!)
  • Peat moss
  • Grass clipping and other debris that you easily obtain from your own garden. Make sure that they do not have seed as you don\’t want to propagate them, and add them directly into the garden bed to decompose slowly.
  • Cover crops or green manure (like clover and vetch) which you can plant on soil that\’s not being use (over the winter period) and then tilled to allow them to decompose. Green manure crops also ensure that the soil is lose and suppresses weed growth.

Doing your homework before diving into planting your crops will ensure that your plants will thrive and give you the results that you desire. There is nothing more frustrating to see all your hard work go to waste because plants do not survive the initial stage because of poor soil conditions which could have been remedied easily.

More Reading:

How to Test the Soil in Your Yard – DIY Home Improvement Guides:


Do You Have Bad Garden Soil?: