|Poorly drained clay soil
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Mixing manure into clay soil
Materials to improve drainage in soil include organic or inorganic amendments. Organic amendments have the added capability of providing additional organic matter and nutrients.
Amendments can include bark and wood chips, compost,and pea gravel, depending on soil type. Note that mixing wood products into soil can tie up nitrogen availability. Additional nitrogen fertilizer may be necessary.
As a result of their high water retention capacity, clay soils often drain inadequately. Materials to improve clay soils differ from those needed for sandy or silty soils.
Cultural practices can also aid in improving drainage.
Adhering to these cultural practices in addition to adding soil amendments can be an effective way to improving drainage.