Clay garden soil is composed of 0-45% sand and silt and 50-100% clay. Clay soil has low permeability and high water retention. Clay soil will absorb less than .25″ of water in an hour and does not drain well, often times resulting in water logging.
The Touch Test- Squeeze a handful of damp clay soil and it will clump together and mold easily.
The goal with clay soil is to improve aeration thus improving drainage and increase nutrients. Add organic material in the fall. Avoid working the soil when its wet. This will prevent large clods from forming. Avoid compacting the soil at all costs. Growing cover crops in the off season can also help in fixing soil.
Amendments such as tree bark, straw, wood chips and peat are good candidates.
The upside of having clay soil is that it naturally has the ability to hold onto a number of trace elements that will benefit a garden.
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