Perpetually wet soils can be remedied if you know what the problem is. Clay soils retain moisture and drain very slowly. Compacted soils are also unable to drain because that have been squished by heavy loads, parking, and frequent foot traffic. I hope the following information will help you navigate through the quagmire of waterlogged soils.
Avoid Sand: It is a misconception that a layer of sand improves drainage but the opposite is true. Sand layers must become totally saturated before they drain to the layer below. It’s much better to mix the sand into the soil rather than lay it on top. Do not add sand to clay soils as it results in concrete.
Add Organic Matter: A much better alternative to sand is organic matter. When it’s mixed into clay soils it build soil and adds nutrients, which sand does not. Mix in fir or hemlock mulch, or use leaf mould to break up the clay and to act as a sponge to soak up the water. Mix it in well and then add a 3 inch layer of an organic mulch over top of the soil. The mulch protects the soil and reduces erosion.
Add Lime: Wet soils don’t retain calcium so they benefit from the addition of lime. Avoid fast activing lime as it’s known to burn soil and plants. Use Dolopril, a coated lime product that is slow release and easier to apply. Before adding any type of lime, get a soil pH done.
Low Areas: Sunken spots collect water, but should drain in a day at most. Filling in the depression with soil is a good way to prevent puddling. For serious low spots that don’t drain convert the area to a pond, bog garden or a rain garden.
Drain the Soil: Another option, is to install a trench (French drain) to move the water away. It is simple but very effective, permanent solution. This low tech method removes water from an area by using a trench and gravity. Look below for construction tips.
Plants that don't mind wet feet
Plant! If you want to go with the flow, so to speak, add plants that don’t mind wet feet. They will also help dry things out: goat’s beard (Aruncus dioicus), Astilbe, water avens (Geum rivale), Gunnera, Japanese iris (Iris ensata), Siberian iris (Iris sibirica), Ligularia, Rodgersia, redtwig dogwood (Cornus sericea), river birch (Betula nigra), swamp maple (Acer rubrum), Persian ironwood (Carpinus persica) and willow (Salix).
Soggy soil, saturated beds and floating lawns are a result of poor drainage. A French drain is a simple, low tech method to removing water from an area by the use of a trench and gravity.
You will need:
An Open French Drain
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