Why Is Friable Soil so Important?

Delicate Snowdrop flowers have grown on friable soil in january
Radka Danailova / Getty Images

Friable soil is soil that has the crumbly texture ideal for the underground activity that is the foundation of success with most plants. For example, it is ideal for:

  1. The root growth of plants.
  2. The uniform development of the "eating part" of root vegetables such as ​potatoes and carrots.
  3. "Goldilocks" drainage: ground that strikes a balance between being sieve-like (that is, having the excessively sharp drainage characteristic of sandy soils), on the one hand, and having the poor drainage of clay soils, on the other.

    Such friable soil is usually termed a "loam." Clay soil (one of the three basic types of soil) can be problematic because it is not friable. 

    When you scoop up a handful of friable soil and squeeze it, it is malleable enough for you to form a clump, unlike an overly sandy soil, which does not allow you to shape it. But, unlike clay, a clump of friable soil easily disintegrates when you try to break it apart.

    Why It Is Important to Have a Friable Soil

    The crumbly texture of friable soils not only permits roots and other underground plant parts to thrive. It also strikes the right balance in terms of drainage. That is optimal ground in which to garden drains well enough that it never becomes waterlogged, while, at the same time, retaining sufficient moisture to provide plants with an evenly moist medium in which to grow.

    The vast majority of plants prefer "Goldilocks" drainage and will perform optimally in friable soils.

    So, in most instances, it behooves you to improve a clay soil and make it more friable. Here are some tips for doing so:

    How to Make Clay Soil Friable

    If you have sufficient time and energy, it is easy enough to make clay soil friable, provided that you have access to organic matter. It is simply a matter of spreading a thick (at least half a foot) layer of organic matter over the ground and working it into the soil as a soil amendment to loosen up the clay.

    Any of the followings can be used as organic matter:

    1. Raked leaves
    2. Grass clippings
    3. Non-meat kitchen scraps

    These and similar materials will eventually decompose in the soil, thereby improving soil structure. Or if you want to hasten the process, use compost. Anyone serious about achieving a friable soil in the garden should become acquainted with how to make compost.

    To work organic matter into the soil, you can use either a shovel (spade) or garden tiller. Some experts now warn, however, against getting carried away with rototilling and doing it more often than is necessary.

    List of Plants That Grow in Clay

    But what if you do not have the time or energy to convert clay-dominated ground into a friable soil? The following are examples of clay-tolerant plants. Not surprisingly, these tend to be plants that come with a reputation of being tough customers. Many are wild plants, which is also to be expected. But there is great variety on this list. You will find examples of trees and shrubs, of ground covers and ornamental grasses, of hardy perennials and tropical plants. You will even see a spring bulb plant listed (as an exception to the rule), although experts generally recommend good drainage for these springtime wonders, or else the bulbs tend to rot in the ground during the winter:

    1. Ash trees
    2. Autumn Joy stonecrop
    3. Bee balm
    4. Beautyberry shrubs
    5. Black-eyed Susan
    6. Butterfly weed
    7. Canna lilies
    8. Common milkweed
    9. Coneflower
    10. Coreopsis
    11. Creeping phlox
    12. Daffodils
    13. Deutzia shrubs
    14. Ferns
    15. Flowering quince
    16. Forsythia
    17. Goldenrod
    18. Hosta
    19. Joe-Pye weed
    20. Lilac bushes
    21. Miscanthus grass cultivars
    22. Ninebark shrubs
    23. Oak trees (generally)
    24. Pagoda dogwood tree
    25. Pussy willows
    26. Red-twig dogwood shrubs
    27. River birch trees
    28. Russian sage
    29. Salvia
    30. Shasta daisy
    31. Spirea shrubs
    32. Swamp maple trees
    33. Viburnum shrubs
    34. Winterberry
    35. Witch hazel
    36. Yarrow