Global menu

The Green pages

Assessing your soil’s drainage

System for evaluating soil drainage.
Photo: Illustration: Audrey Desaulniers
A hole filled with water is used to evaluate the drainage of the soil.

Assessing your soil's drainage is recommended before you get into planting plants. Most plants require a well-drained soil, otherwise their survival is at stake. Fortunately, there are solutions if you are dealing with poorly draining soil.

How to assess soil drainage

Here is a simple drainage test:

  1. Dig a hole of at least 30 cm deep and wide;
  2. Fill it with water and allow it to drain;
  3. The next day, refill the hole with water, then time how long it takes to drain completely;
  4. If the hole drains quickly, you have good drainage. If the hole drains at a rate of less than 2.5 cm per hour, or if there is any water left in the hole after 12 hours, you have poor drainage.

Solutions to drainage problems

If you are dealing with poorly drained soil, you can take one of these measures:

  • Choose plants suited to your growing conditions. Examples:
    • Trees and shrubs : European black alder (Alnus glutinosa), swamp oak (Quercus palustris), redtwig dogwood (Cornus alba), false indigo (Amorpha fruticosa), hackberry (Celtis occidentalis), weeping willow (Salix alba 'Tristis'), creeping willow (Salix repens), etc.
    • Perennials : bergenia (Bergenia sp.), goatsbeard (Aruncus sp.), turtlehead (Chelone sp.), darmera (Darmera peltata), Siberian iris (Iris sibirica), ligularia (Ligularia sp.), butterbur (Petasites sp.), rodgersia (Rodgersia sp.), globeflower (Trollius sp.), etc.
  • Improve the soil structure.
  • Build raised beds.

Add this