Testing for Proper Soil Drainage

112 - Flower Pot.jpg

If you are planning a new flower or plant garden in your yard, or if you simply want to enhance the quality of your garden, proper soil drainage is essential for robust plant and flower growth. Poor drainage is one of the leading causes of failure and frustration for many gardeners. There are many ways that you can improve poorly draining soils. However, you will first need to determine how well your soil is drained. Here is a step-by-step guide to help you determine how well your soil is draining, and tips on how to improve it.

Materials Needed:

  • Shovel
  • Bucket of water or a garden hose

Step 1 - Determine Your Test Area

First, you will need to locate the area where you want to test the soil drainage. If you're planning a garden, you will want to test your soil drainage before you start planting flowers or plants. You should pick an area in your yard that is most suitable for the types of flowers and plants that you want and do your soil drainage testing there.

Step 2- Preparing Your Test Area

In order to prepare your test area, dig a hole in the soil that is approximately 18 to 24 inches deep. This will allow you to pass through the first two layers of topsoil in the earth where you want to test the drainage.

Step 3 - Beginning Your Soil Drainage Test

Fill the hole halfway full with water. There should be approximately 9 to 12 inches of water in the hole. Allow the water to simply sit in the hole.

Step 4 - Gauging the Drainage Results

Depending on the drainage quality of your soil, you may have to look at the water levels in the hole many times to determine the drainage results. You should expect to see the water disappear from the hole within a few hours to a few days. Below is a table of common drainage times that will accurately reflect the quality of your soil drainage:

  • If your soil drains the water in the hole in about four hours or less, your soil has excellent drainage.
  • If the water in the hole is absorbed within four hours to 24 hours, you can consider your soil to be well-drained or above average in its drainage ability.
  • If your soil drains within 24 to 72 hours, you have moderate drainage. This type of drainage will be okay for most types of flowers and plants. It may need to be improved for plants or flowers that are easily damaged by excessive watering.
  • If it takes more than three days for the water in the hole to disappear, you have very poor soil drainage. You'll need to improve the quality of the drainage before planting flowers or plants in your new garden.

If the test results indicate that you have very poor drainage, you may need to dig trenches around your flower or plant garden to help drain the water. You might also need to build up the area where you want to plant, and allow the water to drain downward into an area that is lower than the height of your garden.

112 - Flower Pot.jpg

Photo copyright Wikimedia Commons (