Can Plants Drain a Wet Spot?
Q. We have a high water table, and I am looking for a natural way to make the lawn drier so the kids can play on it. I did some research and weeping willows and junipers seem to be high water absorbing plants. Do you have any other suggestions?
- ---Ravi in Blue Bell, PA
I have several low areas in my yard that collect water after a rain. What tree would you recommend to help soak up the moisture? Thank you,
- ---Phillip in Western Tennessee
My parish (Holy Savior in Westmont, NJ) would like to plant a tree on the grounds, and we were hoping you might be able to give us some guidance. The area we have in mind is in a lawn that always seems to be soggy. Thanks!
- ---Bill in Westmont, NJ
A. Some mature trees can take up a lot of water—50 to 100 gallons a day. But they often return a fair amount of that water back to the ground as a kind of 'sweat' later on. After a recent deluge, for instance, I noticed water hitting me as I walked under several different types of trees, and it wasn't old raindrops; it was coming from the leaves.
So: Are some trees giant sump pumps? Or are they just trying to move enough water away from their roots to be able to breathe again for a bit? Either way, there are real physical limits as to how much water any tree can absorb. When people talk about planting things like willows, eastern red cedar, bald cypress and river birch in wet spots, they're mostly naming the handful of trees that won't die when their roots stay wet for extended periods of time.
That said, those are the big four; all grow in a wide range of climates and can survive dry spells, which is important; a lot of spots that "always stay wet" are actually pretty dry in the summer. So if you want a big spectacular tree in the landscape, like for that church lawn, a moisture lover will likely thrive there. And Mindy Maslin, Project Manager for the Pa. Horticultural Society's "Tree Tenders" program, says that based on her experience, the right tree in the right place might well make the surrounding area a little drier.
But the only sure cure for a wet lawn is to dig it up and install the drain tiles that should have been put in place the first time.
Q. I would like to amend my back yard so that the water drains more slowly to the Brandywine watershed and creates more habitat for wildlife. But I don't know what to plant. It becomes a creek periodically, but gets very dry in summer. I've thought of just "letting it grow" into a meadow but am concerned about weeds. Any suggestions?
- ---Gerallyn in West Chester, PA.
The neighbors' yards all merge towards ours at a downward slope and our back yard becomes a swamp during hard rains. I would like to put in a small pond, but I'm concerned that the liner might be lifted up or the plants washed away when the rains come. Is there some way to have a place for the water when it comes and yet not have the yard look like a swamp the rest of the year?
- ---Lalasa in Roslyn, PA
My yard is lower than the lots on both sides of me and the last 30 feet towards the nearby stream is always wet. My wife does not want a pond, and the only alternative I have to dry this area out is to install 900 ft. of underground drainage tile; and then it would just all dump into the creek! Are there any trees or plants that could help this wet area? Thanks!
- ---Francis in Clark County, Ohio
In one corner of our yard, rainwater stays around for a day or so, then it's muddy for a few days after that. A neighbor suggested I plant a willow tree there to soak up the water. It's about 25 yards away from my house and a stream that runs behind my property.
- ---Michael in Newtown, PA
Twenty-five yards is 75 feet (and people say I'm slow!). That's probably too close to the house for a willow. They love to work their roots into pipes and septic systems and should be at least 100 feet from such temptations. Some sources say 200 feet! ("Do I hear 300?") A much better option for you and your fellow questioners is a "Rain Garden".
One of the hot new trends in green landscaping, rain gardens aren't ponds and don't depend on big trees to suck up moisture. As Mary Ellen Noonan, a degreed agronomist working as Environmental Educator for the Bucks County PA Conservation District explains, they are a type of garden design that uses a systematic set of plantings to lessen the pollution and erosion impact of heavy rain on our fragile waterways. From a homeowner's perspective, they slow down the deluge in a way that preserves the rest of your landscape and creates a horticultural focal point.
Although Mary Ellen touts her rain gardens in Pennsylvania, the trend began in Maryland, quickly became popular in Michigan, Wisconsin and Minnesota, and works just about anywhere. Her ideal rain garden is not located where the puddle problems are now, but in a nearby spot with better drainage, where the water from your downspouts and/or neighboring runoff can be directed.
But Patricia Pennell, Program Director for Rain Gardens of Western Michigan, likes to install the garden right in the problem spot. You just have to excavate a lot of the existing soil during a dry stretch, she explains. (If you think a rain garden is something you'd like to explore, visit their web site; it contains an amazing amount of detailed information.)
Either way, the plan is for future excess water to be captured in the plant-filled, saucer or bowl shaped depression you will create, and then drain slowly into the sub soil.
And the plants? You have many options. Here are a few examples that both of our experts highly recommend:
- Real moisture lovers like turtle head and blue flag iris in the wet middle.
- For the intermediate area, in-betweeners like cardinal flower and Joe-pye weed.
- Then tough plants like Echinacea and Black-Eyed Susan on the often-dry edges.
It's landscaping that helps solve your water problem, keeps our streams cleaner and looks darn good.