Agriculture Reference
In-Depth Information
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Grow your crops on raised beds or berms.
ture or type affects drainage. Unfortunately, there is little you can do to
change soil texture in any but the smallest plantings. Hauling in enough sand
or clay to modify the soil on a large scale is generally prohibitively expens-
ive. What is more, adding sand or organic matter to heavy, low-lying soils
seldom improves the drainage because the water still has no place to drain
to. For example, say you have a slight depression where water stands for a
day or more after rain. Filling the depression with well-drained soil will not
improve the drainage because the water will still perch on top of the heavier
soil at the bottom. This practice simply creates a pot without a hole in the
bottom and can actually make a poorly drained soil even worse.
If you choose to amend your soil with sand and/or organic matter, spread
the amendments across the entire planting area, including alleys, and till
them into the soil. Then lay out your tree rows and plant the trees. Do
not simply dig a trench along a tree row and fill it with amended soil or
add amendments to the planting holes. Doing so creates a boundary layer
between the amended and native soils that impedes root growth and the
movement of water. Again, you have created a pot without a hole in the bot-
tom.
Sand and organic amendments can effectively lighten soils and improve
drainage when combined with raised beds, and such practices can be effect-
ive for small orchards.
Identifying and breaking up hardpans.
Hardpans are impermeable layers of
soil that prevent water from draining through the soil. This limits the move-
ment of oxygen into the root zone, reduces micro- and macrobiological activ-
ity, increases root and collar diseases, and makes certain nutrients less avail-
able to plants. Hardpans also limit how deeply roots grow and can create
weakly anchored trees that experience further root damage as they sway ex-
cessively in the wind.
