Wednesday, July 13, 2016

A Rain Garden is Born

Wow.  It’s been a while since I last scribed some words here.  I just realized I never wrote about the rain garden I installed in the fall of 2014.  So let’s jump back to then.
I’m proud to report I lived up to the promise I made my wife to keep the front yard native garden tidy, deadheaded, and weeded.  Fortunately that work resulted in permission to expand the garden).  After that expansion, can you imagine my surprise when my wife said, “Why don’t you add more space to that garden?”  She saw how long it takes for a native planting to fill in and start looking good.  She didn’t want to lose another year waiting for a project to beautify itself.  But of course she reminded me the same rules would apply.  Tidy, deadheaded, weeded.  No problem!  Within mere milliseconds I was out there laying out the new bed. 
As I looked at the space, I thought I’d try to be a landscape designer.  A winding path between the old bed and this new one would like nice and make it pleasant and comfortable to walk among the plants.  It would also make it much easier to photograph pollinators and flowers.  Knowing I wanted to eliminate as much lawn as possible and maximize the garden space, I measured the width of the lawnmower.  The lawnmower was 19.663456 inches wide.  That’s how wide I would make the path.  Ok . . . I reluctantly rounded it to 20 inches.   
Sod removed from the new garden
With the age-old trick of using a hose to outline the edge of the bed, I marked the border and began removing sod.  My mind now having totally converted to reducing the ecological wasteland of lawn, I was thrilled as each square inch of turf grass came up.  I was using a mattock to strip the grass out of the rock hard clay and that was hard work.  My plan was to shake off as much dirt from the grass roots as possible, and then invert the clumps of sod to use as mulch.  With this in mind, I piled all these clods of grass on a large tarp. 
Over the course of several days I continued to prepare this 25 x 7 foot space for planting.  Once I got down to bare dirt, I drew up a plan to group each of 7 species for a dramatic succession of blooms through the seasons.  Butterfly Milkweed, Blue Vervain, Wild Bergamot, Little Bluestem, Virginia Mountain Mint, New England Aster, and Swamp Milkweed were the plants I chose.  Then it rained and the space became too muddy for me to plant. 
Rainwater flows down the driveway
During one of the downpours I noticed the water ran down the driveway and pooled in one spot at the edge in front of this new garden space.  Once the small pool got filled enough, the overflow moved on down the drive and into the street.  Hmmm . . . I wondered if a small trench at the edge of the driveway could capture this rainwater and move it into the garden.  Could I make part of this space into a rain garden? 
This is too exciting.  I couldn’t wait until the rain stopped.  You’ll remember how impatient I am in things like this.  So, in a raincoat and armed with an umbrella and a small shovel I marched out and dug a tiny 3 inch trench through the grass border.  Hokey smokes.  It worked.  The water moved from the driveway depression into the garden.  Any neighbors observing this must have thought I was trying to recreate Gene Kelly’s dance scene from “Singing in the Rain” as I moved back into the house. 
Reading up on rain gardens and suitable native plants for this lower section of the new garden and with some guidance from my friends at the Rain Garden Initiative, I chose to add some more Swamp Milkweed, and Blue Flag Iris, Dense Blazing Star, and Obedient Plant to the plant list.
Percolation testing
To determine how deep to make this area, I performed the recommended percolation tests by digging three 8 inch deep holes and filling them with water.  Once the water was totally absorbed, I again filled the holes with more water and started measuring the time and drop in water level.  In that dense clay, it took 12 hours for the water to disappear from the holes.  But that was sufficient.  I learned the idea is to collect the water and let the deep-rooted native plants facilitate absorption into the ground thereby filtering the water. 

String level helps determine depth of garden
With percolation data collected, I scooped out a sloping depression of 8 inches deep by 6 feet by 7 feet.  Since this entire bed was in a sloping area, I used a string level to determine how deep I should dig at various parts of the space to get my 8 inch depth.

Sign indicates this is a rain garden in progress
Plants in place, I put my upside down turf to cover all the bare ground.  Ah . . . this really didn’t look good at all.  I knew the neighborhood association would start getting complaints about the unsightly patch in my yard.  To tell the truth, it was UGLY.  What to do?  It came to me in my dreams.  Put a sign up.  So I put together a small sign indicating this was a Rain Garden in progress and included a QR code pointing people to a the Rain Garden Initiative web site that explained rain gardens. 
A few years ago toxic algae blooms in Lake Erie gained us undesirable national attention when our region of half a million people was without water for 3 days while the water authorities wrestled with fixing the situation.  Given the dramatic impact this water quality issue had on all of us getting our water from the City of Toledo, I imagined I’d be busy answering the doorbell.  I’d be fielding questions from neighbors about how they too could put a rain garden in and thereby help filter the algae producing chemicals from our stormwater.  Well it’s a good thing I didn’t set up my desk by the front door because that didn’t happen.  However, the sign did produce questions from neighbors who saw me as I worked in the garden. 

The next summer the garden had started to fill in and was looking ok.  The number of butterflies, skippers, bees, and wasps was incredible.  Already the deep rooted native plants were doing their work.  A friend of mine who deals with stupefying mathematical equations, figured the rain garden portion of this planting holds 209 gallons of water and a one inch rainfall on our driveway produces 582 gallons of runoff.  During a slow to modest rainfall event, all the water goes into the rain garden and it never overflows.  Only twice, in major downpours, have I witnessed the water flow out into the street and then only in a trickle.  This 16 second video clip shows the water flow. 

This totally fascinates me. One day my wife couldn’t find me in the house.  It was raining and she suddenly realized looking out at the front of the drive would solve the mystery.  Sure enough, there I was with an umbrella, watching the rainwater move into the garden.  
What used to take 12 hours for 8 inches of water to be absorbed into the ground, now takes only 2 hours.  Incredible!  All the water that used to quickly run off into the Maumee River laden with pollutants, is now filtered before it makes its way to the waterway, before it reaches Lake Erie, before it’s reclaimed at the Toledo water intake, and before it returns to our tap for cooking and drinking. 

Garden as it looks today - 1  1/2 yrs after starting
Last summer we had an overabundance of rain.  I spent a lot of time under an umbrella at the end of our driveway.  This year we’re in a major drought and everyone is praying for rain.  Bare ground is cracking and trees are dropping their leaves.  Neighbors are watering their gardens and some their lawns.  This 1½ year old native garden is doing fine with only two minor applications from the hose.  Nonetheless, I wouldn’t mind spending some time under the umbrella marveling at the efficiency of this garden’s natural processes that our disappearing wetlands once provided. 
Hummingbird Moth on Wild Bergamot
Northern Broken Dash skipper
The rain garden is loaded with life.  Friends have helped me identify Meadow Fritillary butterflies, Northern Broken Dash and Delaware skippers none of which have I seen here before.  Numerous species of bumblebees, other native bees, and hover flies are always present.  The Wild Bergamot seems to be a favorite of the day flying Hummingbird moth.  Clean water, pollinators, and an abundance of life.  I can’t understand why everyone doesn’t have a rain garden filled with native plants.

Delaware Skipper

1 comment:

Laura said...

I am in the early stages of naturalizing my suburban plot with natives too. I live in a traditional 70's built area in Ontario and there have been some raised eyebrows -- and I have only just started. Can't wait to blow their minds over the next few years (and hopefully inspire, not anger!). My husband's given me carte blanche, since he hates mowing the lawn.

My backyard has a flooding problem due to new builds behind us, and I feel like I am making my backyard into one giant rain garden. I, too, run out in the rain (most recently with a flashlight at night) checking out the flow and my progress.

Cheers to your project!