Here’s a recipe for a landscaping disaster this spring.
First: The soil in your Maple Grove backyard contains a lot of clay—because that’s just how Maple Grove soil is—and as soon as April comes round, rain pours in sheets. “Clay acts as a sponge,” says Tony Poppler, owner of landscaping company Land Escapes. “Clay sucks in the water, so water just sits in there.”
Next: You have a second-story deck, and underneath sits a patio—because that’s just where a lot of backyard patios are in Maple Grove. Gaps between the concrete patio pavers take in the April rain like a sieve. The spongy soil under the pavers gets little sun and little air circulation, sheltered below your deck, so the soil stays packed with water that can’t evaporate.
Then: Summer hits. Heat causes the waterlogged clay to contract. Concrete patios sink. Your deck footings sink. Then, winter hits. Cold causes the soil to expand. Concrete patios rise. Your deck footings rise. April arrives, bringing a ten-inch downpour, and the ground fluctuates even more.
Luckily, Maple Grove backyards have their natural benefits, too. They usually grade down from the house, so rainwater seeps away from the patio and toward city drains. Still, that’s not always enough. A house built in the ‘70s or ‘80s, settled deep in the clay, can actually draw water in if the grade slopes toward the house.
To direct water away from the house and out from under the deck, Poppler dug up the pavers of one such patio last spring. He installed a drain tile system in the ground beneath—a downwardly sloping network of porous, hollow, four-inch tiles that collect water and bring it to the public water line near the bottom of the lawn. Tile coatings block dirt from entering the pores so the tiles dispense clean water.
But let’s say your backyard also features landscape rock buried into the soil. Pretty, but they keep rain from following a yard’s declivity. “Picture a pile of rocks,” Poppler says. “If you drip water on that pile, it runs straight down. There’s a lot of airspace between the rocks, whereas if you have a pile of dirt, there’s little airspace.” That tight airspace between granules makes soil a flat surface, where, instead of dripping vertically, water slides along the lawn’s curve.
So, if rocks surround a house, Poppler often removes them and puts in more soil to keep rainwater running slantwise.
Of course, Poppler also deals in the less stressful sides of spring softscape. He helps homeowners determine which plants suit their yards—light-colored daisies in sunny spots and philodendrons in the shade, for instance. He lays mulch under pine trees, whose droppings of acidic needles kill grass but help hydrangeas and rhododendrons thrive. He brings pavers in dump trucks and constructs patios.
Still, while he paved Adam Carlson’s patio in April, 2016, water once again posed a problem.
Carlson lives near Central Park of Maple Grove. Before squeezing the concrete pavers into their cubbies of sand, Poppler pulled up the irrigation line that would have sat directly under Carlson’s new patio. The line formerly fed water to a couple of sprinkler heads. Poppler capped the line to avoid leakage.
Another bane of rain came next: erosion. Last summer, two big storms powered through Maple Grove. Water slid off Carlson’s house, thundering into the patio. Rain gushed down the gently sloping lawn, and sand from around the pavers piled up along the edge of the grass.
Poppler suggested Carlson install gutters to funnel the rain off his roof. This way, sand around the pavers stays put and out of city drains. To save soil from erosion, Poppler uses retaining walls.
Poppler waits until May for large projects. “Roads are spongy,” Poppler says. In winter, water absorbed in the roads freezes, making them susceptible to cracking under the weight of semis hauling concrete pavers.