After recent rainstorms, yard drainage is key
We now own waterfront property.
My wife and I watched a new stream flow through our side yard and feed a rising pond in the back. It didn’t last long enough to stock it with fish, but the weather has kept our soil saturated for days.
Several plants have struggled because their roots require oxygen to properly function. Wilting can occur when the soil is saturated, especially when it’s hot. Plants are attempting to transpire but the root activity is limited.
There are times when a shrub has been planted in clay and wilts due to transplanting shock and low soil oxygen. Sometimes it will drop leaves. This is referred to as wet wilt. If the cause is not investigated, a homeowner will add more water.
There’s nothing you can do about the weather, but you can remedy your property.
Some plants thrive in wet conditions, even grow in standing water.
Consider perennials such as iris, umbrella grass, swamp hibiscus, Northern sea oats or canna.
Water-tolerant shrubs include inkberry, sweetspire and leucothoe.
Water-tolerant trees include swamp oak, black gum and willow oak. Bald cypress, too, but the knees can be a problem in residential areas.
Go to Clemson’s Home and Garden Information Center for a complete list (www.clemson.edu/extension/hgic).
If your soil is heavy or poorly drained, there are a couple of other options.
A clay hole can hold water like a container. Instead, plant on berms. Topsoil can be shaped into sloping mounds to allow water to drain properly and roots to quickly establish. In some cases, an entire berm does not need to be constructed but rather generously mounded for a tree or shrub.
Drainage systems can be installed to lower the water table or allow water to percolate through the soil. Tile drains utilize perforated corrugated pipe, called drain tile, to capture and remove water. That name is confusing because we’re actually talking about flexible drain tubes, or pipes, not square pieces of tile.
However, the original drain system utilized clay tiles, and even though we now use plastic tubing, the name remains drain tile.
Perforated drain tile is typically four inches in diameter and allows water to enter through small slits that surround the entire pipe. They are sometimes sold with a geotextile sock to filter out contaminates to keep the drain tile functional for a longer period of time.
Some newer drainage products wrap the drain tile inside a sleeve of Styrofoam peanuts to make installation easier and more effective.
Trenches are typically eight inches wide and should drop about an inch every 10 feet for suitable flow.
Once the fun of digging is finished, a couple of inches of drainage stone is placed on the bottom. Angular drainage gravel, such as No. 57 stone, provides plenty of pore space for percolation.
The drain tile is placed in the trench and covered with the remaining gravel with a minimum of two inches on top. If the Styrofoam peanuts product is used, the drainage gravel isn’t needed.
It’s important that the drain tile be sloped toward an outlet where water can be discharged, such as a ditch or pond and not your neighbor’s yard.
For many people, this is the main obstacle: no suitable outlet. That’s where French drains can be helpful.
The French drain is a gravel-filled trench. Since it doesn’t contain drain tile, it has no outlet. It’s designed to facilitate water movement off the surface and into the ground.
The trench can be any dimension you want, but it’s typically eight to 24 inches wide and up to 36 inches deep.
The trench is sometimes lined with weed fabric before it is filled with drainage gravel to filter out sediment to slow the clogging of pore spaces. In nonturf situations, it can be filled to the surface with gravel.
Drainage systems aren’t permanent solutions, but they can be effective for several years or longer, depending on conditions.
Tony Bertauski is a horticulture instructor at Trident Technical College. To give feedback, email him at firstname.lastname@example.org.