If your soil contains a lot of clay, you will probably need a large rain garden. If you have sandy or loamy soil that absorbs water quickly, plan on making the garden about eight to 10 inches deep. Put the rain garden in a natural low spot that fills with water after a storm, if possible, and in an area that gets a half to a full day of sun.
How do I create a rain garden?
Remove any lawn or other vegetation from the spot where you'd like to create a rain garden. Clay soils work best because they have a slower percolation rate, allowing water to slowly drain. If you are unsure of the type of soil you have, complete a soil test, which can usually be done for a small fee through your state's extension service.
How to choose the right soil for your rain garden?
Your soil type helps determine the minimum size of your rain garden. Clay-based soil is slow to drain, so it will need more surface area; sand is fast-draining, so it can be small but effective; loam soils are average drainers. However, with the addition of sand or other substrates, loam-based rain gardens can improve their absorption rates.
How do you prepare soil for a raised garden bed?
Fill all but the top 6 to 12 inches of the excavated area with rain-garden soil. Slope the sides gently. If the soil you excavated is relatively free of clay, you can use a mixture of 65 percent native soil to 35 percent compost, or 2 scoops of soil for each scoop of compost.
How do you keep rainwater out of your yard?
Pay attention to yard areas that catch most of the runoff from the house roof and downspouts. If possible, build your garden within 30 feet of the downspout or roof drainage for maximum efficiency. Keep the rain garden at least 10 feet from your home’s foundation to avoid water seeping into your foundation walls.
How deep should a rain garden be in clay soil?
6 inchesClay soils absorb water more slowly than sandy soils. To avoid drowning plants in clay soils, the garden depth should not exceed 6 inches. Heavy clay soils can be amended with compost to speed drainage. Rain gardens located in more sandy soils can be up to 8 to 12 inches deep.
How do you make a simple rain garden?
2:046:03How Do I Build a Rain Garden? - YouTubeYouTubeStart of suggested clipEnd of suggested clipStarting with the highest edge. And working around the garden. With a string at the base of theMoreStarting with the highest edge. And working around the garden. With a string at the base of the highest stake use a string level to mark the height on each stick around the perimeter of the garden.
What type of soil is best for a rain garden?
A good mix for a rain garden is 30% sand, 30–40% loamy topsoil and 30% organic material from yard waste compost. This mixture must be tilled into the existing soil to ensure proper drainage conditions.
How do you make good drainage in clay soil?
Because clay soils hold water, creating raised beds can help improve drainage by encouraging water to run off. Raised beds can be a simple mound of soil, or can be constructed out of wood, brick, or stone. To lessen compaction, size the beds so you can reach the middle without stepping in the bed.
What materials are needed for a rain garden?
Materials Required1-1/2-in. river rock.Decorative rocks and boulders.Landscape fabric.Native plants and grasses.PVC pipe.
What are the different layers of a rain garden?
The rain garden consists of a vegetated or stone ponding area, a mulch layer, a planting soil layer, a sand bed, and a gravel base. The multiple layers work together to filter pollutants from water, allowing it to infiltrate into the groundwater supply uncontaminated.
Where is the best place to put a rain garden?
The rain garden should be located in a place that can collect as much impervious area (driveway, roof, sidewalks) runoff as possible. The best areas are generally where water naturally drains but doesn't hold water. It should also be located at least 5'-15' away from your home.
Can a rain garden be on a slope?
The rain garden can be constructed on a slope, but more digging will be necessary to produce a level bottom (fig. 3). Areas where the water table is high or the land is often saturated are not good options. Additionally, rain gardens should not be located over a septic system.
What is the point of a rain garden?
A rain garden is a depressed area in the landscape that collects rain water from a roof, driveway or street and allows it to soak into the ground. Planted with grasses and flowering perennials, rain gardens can be a cost effective and beautiful way to reduce runoff from your property.
How do you fix clay soil that won't drain?
0:042:50How to Drain Clay Soil : Green Savvy - YouTubeYouTubeStart of suggested clipEnd of suggested clipWhat I'd encourage you to do is to actually increase the depth of your mulch up to about 6 inches.MoreWhat I'd encourage you to do is to actually increase the depth of your mulch up to about 6 inches. So it can absorb a lot more water. So that's a quick and easy fix.
How do you garden in clay soil?
Before planting in spring, add compost and aged manure. A 2- to 3-inch layer worked into the soil to shovel depth is a good amount. Be sure to add at least a few weeks before planting to allow the material to break down. Use mulch to help reduce compaction of your clay soil from hard rainfall.
Can you add sand to clay soil to improve drainage?
Unfortunately, it doesn't work that way. When sand mixes with clay, it creates a soil structure akin to concrete. To create a real change in a clayey soil structure, you would need to add a 1:1 ratio of sand to clay. Considering the actual volume of clay soil underfoot, that equates to a lot of sand.
How to make a rain garden with a flat bottom?
Create a flat bottom so that water will percolate down evenly. If the rain garden is on a slope, you can pile some of the excavated soil into a berm on the low side to retain the water. For stability, stomp the berm soil down well and make the base at least 2 feet wide and the top at least 1 foot wide.
How does a rain garden work?
The plants and amended soil in a rain garden work together to filter runoff. Generally, a rain garden is comprised of three zones that correspond to the tolerance plants have to standing water; the better a plant can handle "wet feet," the closer it is placed to the center of the garden.
How big should a rain garden be?
If you want an impressive-looking garden, make it at least 150 square feet. Ovals, kidneys, and teardrops often look best, but rain gardens can also be long and skinny. Use a garden hose to test possible shapes. Once you settle on a design, decide where the water will flow in and where any overflow will exit.
What plants can tolerate standing water?
The middle ring, Zone 2, should have plants that can tolerate occasional standing water, like Snowberries ( Symphoricarpos albus ).
What do you need to know before building a rain garden?
Before you build a rain garden, you need to decide where you will be placing your rain garden. Where to place your rain garden is as important as how to build a rain garden. There are a few things to keep in mind when deciding where your rain garden will go.
How to determine the depth of a rain garden?
Keep in mind when determining the depth of your rain garden that the depth starts at the lowest edge of the garden. If you are building on a slope, the lower end of the slope is the starting point for measuring the depth. The rain garden should be level across the bottom of the bed. Once width and depth are determined, you can dig.
What is a rain garden?
Image by Roger Soh. Rain gardens are quickly becoming popular in the home garden. A pretty alternative to more conventional methods of improving yard drainage, a rain garden in your yard not only provides a unique and lovely feature, but can also help the environment.
Do rain gardens need a downspout?
Many rain garden plants work best in these conditions and full sun will also help water move on from the garden. Access to a downspout – While you should not place your rain garden near the foundation, it is helpful for water collection if you place it where you can extend a downspout out to it. This is not required, but is helpful.
How to make a rain garden?
Plan and Plant Your Garden. In the final step to make a rain garden, arrange your plants, spacing according to label directions. Water well and mulch. As you choose plants to make a rain garden, consider planting in larger drifts for best overall impact.
What soil is best for a rain garden?
Clay soils work best to make a rain garden because they slow the percolation of water, holding water while allowing it to slowly drain.
Why are rain gardens important?
Rain gardens are both beautiful and practical: They filter rainwater runoff and provide a home to birds and butterflies. Plus, they're easy to maintain. Here's how to make a rain garden in five easy steps. Use your rain garden to manage runoff in an urban garden—and find even more inspiring ...
Why do we need rain gardens?
Rain gardens filter runoff and protect groundwater, especially after big rains. They also add unexpected beauty to low spots that tend to collect water and draw wildlife. Here's how to make a rain garden in your own landscape. By Kelly Roberson. Updated May 13, 2019.
What plants can grow in a rain garden?
Those plants include 'Bengal Tiger' canna, scarlet rose mallow, yellow flag iris or Siberian iris, cardinal flower, and obedient plant.
Can you plant native plants in a rain garden?
As you make a rain garden, stick to plants that can tolerate wet sites. Many native plants work best, and seedlings are easier to establish than direct-sown seed when you are going to make a rain garden so you don't have to worry about the seed washing away. For that reason, native plant plugs work better than seeds.
What is a Rain Garden?
Put simply, a rain garden is a purposely-built area of a yard designed to facilitate drainage. In some circumstances, soil erosion and compaction create areas of the yard that no longer drain. When it rains, these areas allow storm runoff (sometimes polluted) to collect in low spots of a yard.
How Does a Rain Garden Work?
Installing a rain garden is like adding infrastructure to your yard. The strategic placements of shrubs, plants, and trees create a root system that absorbs water and passes the nutrients along to the plants. This helps create a natural water cycle that allows for proper drainage and natural growth.
How to Build a Rain Garden
One of the most attractive features of a rain garden is how easy it is to build. With minimal maintenance required, a rain garden will thrive as nature intended. But as with any successful project, research is key and requires a bit of planning before you break ground.
Selecting a Location for the Rain Garden
First, you need to choose a location. A popular spot is near a downspout where the ground slopes away from the house. Some gardeners even create a swale (small river bed) that leads from the downspout to the rain garden. It is usually covered by rocks to prevent soil from washing away.
Decide on Size and Shape
Rain gardens come in many different shapes and sizes, so this part is largely up to your personal taste. The size should be whatever is appropriate for the site, though bigger is better if you live in a high rainfall area.
How Well Does Your Soil Drain?
The ponding area of a rain garden needs to be deep enough to hold water, but it is not designed to hold that water for more than 24 to 36 hours. Both the ideal depth and construction method depends on how well your soil drains. Sand drains quickly and clay drains more slowly.
How Deep Should Rain Gardens Be?
Ideally, the rain garden is designed so that water from a heavy rain storm does not overfill the garden. Many tutorials will tell you to dig according to a calculation made using the square footage of your roof and/or driveway, as well as the expected rainfall in your area. For the purposes of this tutorial, we’ll keep things simple.
Amending the Soil
There are two ways to amend the soil in the rain garden. If you soil drains well and grows plants well, you don’t have to do any amending.
Digging Sloped Sides
Dig the sides of the garden so they have a gradual slope that runs from the edge, to the bottom of the hole. This allows water to flow into the garden gradually without soil erosion, makes planting easier and it decreases the risk of trips or falls.
The Inlet and Outlet for a Rain Garden
A proper rain garden should include an outlet and may benefit from an inlet, which is just a fancy way of saying that there should be a couple of little dips at two ends of the garden that allows water to flow in when it rains and out when it gets too full.
What is the purpose of rain garden soil?
Rain garden soils act like sponges that soak up water while also letting the water pass through to the native soil layers below the rain garden. In order to do this, they need to have a mixture of high organic content and sand to improve the coarseness and texture of the soil.
What is the foundation of a rain garden?
The soil, therefore, is the true foundation of how the rain garden functions. The soil has to be graded, or shaped, so it can act like a container, and the soil has to have the right composition for the water to slowly infiltrate it.
How long does rain water hold in a rain garden?
Rain gardens slowly drain rainwater and should not hold water for more than 48 hours. Therefore, it’s critical that the soil mix in the rain garden allows for adequate infiltration. If your existing soil did not perform well in your infiltration rate test, here are two approaches to creating the correct soil mix.
Why do rain gardens work?
Rain gardens function by allowing water to slowly infiltrate the soil instead of running off into city storm drains or contributing to flooding on a property . They act like shallow, permeable containers that drain water through their flat bottom and back into the soil.
Where is the inflow source in a rain garden?
The inflow source, where the water enters the rain garden via a swale or an underground pipe, should be located higher than the overflow point, which is a small outlet that allows excess water to escape during big rain events, set at the top of the ponding depth of the rain garden (see diagram below).
How to make a rain garden?
Create the rain garden by building a berm in a low spot in the yard, then build swales to channel runoff from the gutters and higher parts of the yard. The water is then absorbed into the soil through the network of deep plant roots. Use a mix of plants adapted to your area and to the different water depths. Step 2.
How to channel water from a downspout to a rain garden?
Lay attractive river rock (1-1/2 in. diameter and, if desired, larger decorative rocks) or run an underground 4-in. PVC pipe to channel water from a downspout to your garden. Use PVC for a better flow if the garden is more than 30 ft. from a downspout. Place your rain garden at least 10 ft. away from your home.
How long does it take for a rain garden to drain?
Since your garden is designed to drain in 24 hours, the moisture-loving plants will soon be left high and dry. While almost any plant with the right moisture requirements will do fine in a rain garden, there are some good reasons to select native plants.
How to determine the size of a garden?
To determine the best size for your garden, estimate the volume of water that would flow off the roof and down the spout that feeds it during a 1-in. rainfall (the rainfall from an average storm). To do this, calculate the rough area of the roof that drains down the spout.
Why do we need a rain garden?
A rain garden also reduces the amount of lawn chemicals and pet wastes that may otherwise run off into local lakes and rivers. In some communities, the runoff problem is so big that homes with rain gardens qualify for a tax break! Call your municipality to learn your local policy.
How to keep water away from my garden?
Create an overflow zone, a slightly lower area on one side with stones that will channel water away once the garden fills. Locate it away from your house and your neighbors' homes as well.
What are some examples of rain gardens?
Aster, daylily, iris, sedum, coneflower, artemisia and sedge are examples of good rain garden specimens. Talk to your local university extension or other garden experts about other options for your area. Choose plants that have “average to moist” water requirements listed on their tag.
