Create a Beneficial Rain Garden: A Mini Wetland Habitat for Birds
When the oceans first formed on this planet they held a certain amount of water. Today we still have essentially the same amount of water as then, but as of 2010, humans are using a whopping 60% more than in 1960. In some areas, water is being pumped out of the ground about 35% faster than it is being replaced. Add to this the huge amount of storm water runoff that is the largest source of water pollution we have, and you can see that something major has to be done, and soon.
Beneficial rain gardens have become wildly popular with home gardeners as well as local and state governments, because this type of garden can go a long way toward returning naturally purified clean water to our planetary system.
What Is A Rain Garden?
Simply put, a rain garden is a depression in your landscape filled with native trees, shrubs, grasses and/or wildflowers. Plant roots soak up rainwater, and the excess percolates slowly through the soil. It is filtered and cleansed on its journey to our natural underground water storage known as aquifers. *
*According to Encarta, the online dictionary, an aquifer is defined as a layer of permeable rock, sand or gravel through which ground water flows, containing enough water to supply wells and springs.
What Do Rain Gardens Do?
Once upon a time there was grass and forest as far as the eye could see. Then humans began to build. They built houses, garages, condos, paved roads, patios, driveways, parking lots; well, you get the idea. Hard surfaces replaced earth, grass, fields and forests. So where does the water go when it rains? It runs right down your driveway and into the street and storm drains.
And what does this runoff water carry with it? Pollutants, chemicals, garbage, plastic, phosphorus from fertilizers, pesticide residues, antifreeze from vehicles, rust and dust from vehicle brakes, heavy metals and disease-carrying bacteria and viruses from animal waste, and so on.
Now where do those storm drains lead? To the city water treatment facility, streams, lakes, rivers or the ocean.
Removing runoff rainwater from storm drains helps to keep them from being overwhelmed in a drenching rain situation. We’ve all seen the news reports about rescuers having to help stranded motorists whose cars have stalled in deep water. According to the National Weather Service we can expect more and more powerful rain storms. That means more downpours, more street flooding, more pollutants ending up in our water, more motorists and rescuers at risk, and sky-rocketing insurance rates, and costs for cleanup, etc.
As rain falls through the pollutants in the atmosphere, it collects them. These airborne baddies will be automatically filtered through the soil in a rain garden as well.
What Are the Benefits of Planting a Rain Garden?
Did you know that as many as twelve times more birds are present in wetland habitats than in their dry counterparts!
Meet some of the many bug-eating birds in the table below. Lots of beneficial insects and small animals enjoy rain gardens. Even though they are rich in bugs, there is no long-term standing water, so there’s no fear of mosquitoes in a rain garden. Additionally, these gardens are generally maintenance free. Most weeds do not thrive in wet conditions. Yes, a virtually no-weed garden is actually possible!
You may be asking:
Is it really all that helpful? I mean, what can my little rain garden do? And the answer is: PLENTY!
The example I found is for Tennessee, which has an annual average rainfall of 50 inches. Say your roof covers your 1,100 square foot house. If you build a rain garden that is about 18’ x 14’ x 6” deep and direct the rainwater from just one downspout to your garden, it would collect and filter roughly 18,000 gallons of water in an average rainfall year! That’s just one rain garden and only one downspout.
Meet some of the many birds that belongs to Nature’s Organic Pest Control Team
Favorite Insect Meals
grasshoppers, crickets, beetles, larvae, moths
beetles, grasshoppers, leafhoppers, stinkbugs, snails
aphids, whitefly, scale, caterpillars, ants, earwigs
larvae, caterpillars, beetles
tree borers, caterpillars, ants and earwigs
spiders and tiny insects
caterpillars, larvae, beetles, grasshoppers
small insects and spiders
various insects living under tree bark
moths, beetles, grasshoppers
beetles, grasshoppers, flying insects
aphids, leafhoppers, caterpillars, beetles
caterpillars, aphids, whitefly
larvae, beetles, weevils, borers
grasshoppers, flying and crawling insects
Test For Soil Drainage
Dig a hole 6” to 12” deep and 4” in diameter; fill with water and let stand for about an hour to pre-soak your soil; fill the hole back up with water and measure the depth with a ruler; wait an hour and measure again. The water level in the hole should have dropped at least half an inch, if not more, in that time in order to pass the drainage test.
What Do You Need to Make a Rain Garden for Birds?
Basic Requirements of Rain Gardens:
- The right location. Ten feet away from basement, or 5 feet away from slab; away from your septic field and water well; away from large tree driplines. Rain gardens can be created in sunny or shady spots; just so long as you use the right plants for your particular situation, your bird rain garden will do its job very efficiently.
- Good drainage. This way the water that normally runs off in a storm will be directed back down into the ground to replenish aquifers. Clay soils work best to make a rain garden because they slow the percolation of water, holding water while allowing it to slowly drain. If you have clay soil, it must be amended with compost, organic matter, sand, and/or peat moss to increase its water absorption ability. Slowly work the amendments into the clay soil when it is not slimy wet. On the other hand, trying to work with rock-hard clay is no joy either. Choose a day when your clay soil is neither soggy, nor concrete dry!
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. If your test indicates sandy soil, you will need to add water-absorbing compost and topsoil to the rain-garden area.
- The correct size for best efficiency. The size should be approximately one-third as large as the surface area that drains into it (such as your roof). Typically a rain garden is between 35 and 300 square feet, and a depth of 3 to 8 inches. Rain Garden Size Calculator
- Overflow capability in extreme rainfall situations. This means a notch in your berm, which is the soil, rocks or sod surrounding your rain garden that holds everything in place.
- Plants that tolerate wet feet as well as drought conditions. The native grasses, wildflowers, shrubs and trees know how to cope with your region's climate and soil conditions. They will also attract the most birds and beneficial insects. It’s quite probable that migrating birds as well as those just ‘passing by’ will see your rain garden as an oasis, and drop in for a visit!
Good choices for rain garden plants would include those that like to grow at the edge of ponds, such as:
Rose mallow, flag iris, cardinal flower, obedient plant, cattails, sedges, tall grasses, and turtlehead.
Excellent How To Video from St Louis County, Minn.
How to Create a Rain Garden Step by Step
Step 1 Mark out your proposed garden with stakes and string according to the size you have determined. Be sure to check with your local utility companies before digging anywhere on your property. They’ll be glad to come and mark out any pipelines or electric services that you need to avoid. You don’t want to be the cause of a neighborhood blackout!
Step 2 Dig out the area to your desired depth, keeping the ‘floor’ of the rain garden as level as possible. Use a carpenter’s level and a 2”x4” piece of wood to accomplish this, by moving it around the ‘floor’.
Step 3 Fill your depression with amended clay soil or good loam that has passed the drainage test.
Step 4 Construct your berm by building it up to the desired finished height with soil, flat rocks or sod. To make sure your berm is as level as possible, pound a long stake into the center of your rain garden. Measure up the stake 6”, or the desired finished berm height, and attach a string at that mark. Stretch the string out over the berm to find any low or high spots.
Step 5 Make a “V” notch in your berm to provide for water overflow. Locate this so that it will spill over into your lawn and spread out. You can fill this notch with gravel so water can filter through easily.
Step 6 Shop for plants! And pay attention to their size and width at maturity as noted on the plant tags. Also make sure their light requirements are the same as the sunlight you have available in your new garden.
Step 7 Install your plants.
Step 8 Water your new garden thoroughly to give it a good start, and add mulch. Weeding may be necessary occasionally to begin with. After the second year, your plants will fill in and spread, eliminating the need for most weeding.
Step 9 Register your rain garden. Why register it? Rain garden registration sites are able to track the amount of rainfall in your area and calculate how much your garden is absorbing. See Link Below.
Go Here to Register Your Rain Garden
- Rain Garden Alliance - Registering my Garden
Community Rain Garden Project Information
- What is a Rain Garden?
Everything you want to know about rain gardens and how easy they are to install in your yard, school, place of faith, government building or business.
Do You Live in the UK?
- The UK Rain Gardens Guide, managing water in our towns and cities
Rain gardens offer the opportunity to citizens to work with nature and participate in the way we manage water in our towns and cities.
Grant Programs for Rain Gardens
All of the States I checked have rain garden grant programs of some sort in place. Each State’s websites also have lists of native plants that do well in different situations. For instance, coastal areas require different plantings than those in the mountains. Additionally, lists of suitable trees, shrubs, grasses and wildflowers for shady as opposed to sunny areas are also helpful. Lots of Universities had information, helpful videos and many other resources for building rain gardens, too.
Check with your State’s Department of Environment and Conservation to see if they have funds and/or information available to help in your rain garden building efforts.
Remember that with a rain garden you will have no mosquitoes, no maintenance, no mowing, no weeding, and no regular watering. What you will have is the enjoyment of a beautiful yet practical garden filled with a large variety of beneficial insects, butterflies, and of course, birds that will visit and thrive. And best of all, know that you had a hand in restoring natural habitat balance, not to mention clean water, to our planet!
Sources: New York State Dept. Of Environment and Conservation; Tennessee Dept. Of Environment and Conservation; Wikipedia and Connie Smith (a/k/a Grandma Pearl)