Rain garden II - The costs

Part I summarizes my rain garden construction process.  I made the mistake of not pricing out everything before beginning the project. Before you commit to a rain garden, you should probably estimate the costs by choosing your garden size, determining whether (and how much) soil will need to be replaced, and either spending a couple hours calling local companies for materials pricing (large jobs) or checking a garden supply store (small jobs).  Also, be sure to check whether your locality provides monetary help.  Your local soil conservation district is a good place to find that out.

The vast majority of our costs, and a lot of the time commitment, arose because our site was heavy clay and all the soil had to be replaced.  Our rain garden is about 220 square feet.  We dug out the clay to 3-4 feet down because soil maps indicated that this depth would hit a better draining layer of soil.  This meant we had to remove and dispose of 30 cubic yards of clay and replace it with new soil.  Disposing of clay didn't cost us directly, since we used it to build up low areas rather than having it hauled away.

The materials prices I list below are typical for my area and for the volumes I was purchasing.  Plant costs were lower because I propagated some myself and was given others for free.  Costs would be about triple if I bought everything at plant sales.

Blue flag iris bud in the rain garden.  (Picture taken in May.)

Monetary costs:

• Mini backhoe rental, 1 weekend (including delivery/pickup) - $300
• Replacement soil, 30 yd (incl delivery) - $1300
• Hardwood mulch, 13 yd (incl delivery) - $400 (Only about 25% is for the rain garden itself.  50% is to help stabilize disturbed areas where we disposed of clay, and the remainder is for other projects.)
• Grass seed and straw - $30 (For parts of yard that were disturbed and/or where we disposed of clay.)
• Plants - $170
• Seeds and supplies to propagate more plants - $20 (Mainly spent on small plastic pots.)
• Satellite dish reinstallation - $100 (It was originally located in the middle of our rain garden site.)

Time:

• Digging out 30 yd of clay with mini backhoe and moving it to roughly the right location - 13 hrs
• Preparing locations to receive clay - 8 hrs (Removed spilled concrete from house construction, and driveway gravel that had washed into low spots.)
• Raking clay smooth after it was dumped by backhoe - 5 hrs
• Rearranging new soil after it was delivered - 7 hrs
• Propagating and tending plants destined for rain garden - 6 hrs (Spread over many months so not a big deal.)
• Internet/phone research to source equipment and materials - 3 hrs
• Building berm on downhill side of garden - 2.5 hrs
• Mulching garden - 1 hr
• Planting - 4.5 hrs 
• Repairing damage after first rainstorm - 1 hr
• Not listed:  Book/internet research on rain gardens and plants; shopping for plants (since these were the fun/hobby parts of the project)
• Also not listed:  Further cleanup of areas where clay was disposed (mulching, reseeding, transplanting)

Tools we used:

• Miniature backhoe (rented)
• Stakes, string, and spirit levels - ensuring that bottom of garden is flat and that berm/edges of garden are all at the same height
• Shovel
• Garden rake
• Trowel - for planting smaller plants
• Mulch fork
• Work gloves - makes a huge difference in number of blisters incurred
• Garden hose - deciding and marking perimeter of garden before digging
• Watering can

Rain garden I - The process

This is the first in a series of three posts about building our rain garden.  The rain garden is supposed to be a well drained bed of moisture loving plants that catches and absorbs storm water runoff.

This post is not meant as a how-to guide; you can find those elsewhere.  The main resource I used was Rain Gardens:  Sustainable Landscaping for a Beautiful Yard and a Healthy World by Steiner and Domm.  It has a Midwest focus, but I found it informative and inspiring.  For Virginia specific info, see this page from the VA Dept. of Forestry and links therein,  a rain garden guide for northern Virginia, plant recommendations from the VA Cooperative Extension, and various other online resources.

On to the fun part, pictures!  These are clickable for larger versions.  (Please excuse the blue tarp in most of the pictures.  It is covering our generator, which is waiting for installation.)

We used a hose to decide on the location and shape of the garden, then marked the edges with spray paint before digging.

This part of the yard was solid clay, so it had to be replaced with well drained soil.  We rented a miniature backhoe to dig out the clay.  Here is the final hole.

We used the extra clay to re-contour our side yard and make it more even.

A dump truck brought 30 cubic yards of replacement soil, a 50/25/25 mix of topsoil/sand/compost.

We leveled the main part of the garden and built a berm on the downhill part to hold the water in (with an overflow pipe to release excess).

After mulching the garden, I finally reached the fun part of the job, laying out and planting the plants.

Getting an "after" picture has been a moving target, since I keep adding more plants, and since we've had some things wash out and need repairs.  Plus of course the plants are still growing.  This picture will have to suffice for now.

Link roundup

Here are several weeks' worth of interesting stuff...

• Growing native perennials from seed from Native Plants and Wildlife Gardens:  This is New England focused but has some good tips.  Propagating your own plants from seeds is a lot cheaper than buying from plant sales.  For your first try, I recommend cardinal flower (Lobelia cardinalis), which has an unusually high germination rate for a native plant.  Its beautiful red flowers are great for hummingbirds.
• What it takes a nursery to stock a plant from Beautiful Wildlife Garden:  Ever wonder why nurseries don't carry more native plants?  This blog entry explains the steps in growing a plant until it's big enough to sell and discusses how much demand is necessary to make it profitable for nurseries.
• Embrace the clay! from Native Plants and Wildlife Gardens:  Here are some plants that actually like clay soil.  All of these except the coneflower are native to Virginia.
• Aruncus dioicus ~ A treat for pollinators from Native Plants and Wildlife Gardens:  Apparently I read this blog a lot?  Anyway, this is another VA native plant.  The blog entry explains how versatile it is as an ornamental.  I haven't noticed a lot of pollinators on my own, but it's still a nice plant.
• Thomas Rainer:  Interpreting nature from View from Federal Twist:  This summarizes an interesting talk by Rainer about designing self sustaining plant communities with different layers.  The post includes some pictures of doing this in a suburban setting.  Making it look orderly enough for suburbia is an interesting challenge.

Pollinator planting guides

This site has guides on Selecting Plants for Pollinators that are tailored to specific ecoregions.  If you enter your zip code, it'll take you to the one for your region.  This is handy because Virginia is divided into multiple ecoregions depending on how far east/west you are.

(HT:  American Beauties Native Plants)

Soil and water conservation districts

Most of Virginia is divided into soil and water conservation districts.  You can find a list of districts here.  My own district is the Colonial Soil and Water Conservation District.  I got in touch with them because of some significant drainage and erosion problems in our yard.  I am building a rain garden, which is a well-drained bed of plants that will catch the runoff and use it rather than letting it flow through our yard.  (You will read a lot more about the rain garden in future entries here, as I plan to use exclusively native plants.)  My district does not help financially with individual homeowners' projects but is happy to provide advice.  Some other districts, such as the Thomas Jefferson district covering Nelson, Albemarle, Fluvanna, and Louisa counties, actually provide financial assistance with building a rain garden, converting turf to a native plant meadow, and other projects.

Last fall, a soil expert came to my house to assess the site and our drainage problems.  This is a nice free service.  Based on soil survey maps of the area, he determined what type of soil we have and then could recommend how deep we have to dig the rain garden to reach soil with better drainage.  He had tips on how to install overflow pipes and where to buy inexpensive mulch.  He was very willing to walk up and down our slope to see all our problem areas and recommended how to deal with each.

Eroded trench in my yard (with tape measure in inches for scale).

One caveat is that the soil expert didn't seem interested in promoting native plants and avoiding invasive ones, so I have supplemented with my own research.  Still, it was a helpful visit.  I would recommend checking out your local district if you have erosion problems and want advice.

Link roundup

I mentioned Dicentra (bleeding heart) in my last post.  Beautiful Wildlife Garden has a nice post about native bleeding hearts, which apparently are a good food source for hummingbirds.  I was pleasantly surprised to see a ruby throated hummingbird checking out my nonnative bleeding heart last week, so I guess that's not a total fail even though it isn't native.

Going further back, there was also a recent post on Beautiful Wildlife Garden about black gum as a shade tree.  There is actually a black gum cultivar ("Wildfire") with particularly attractive fall color.  For people who don't want to plant yet another maple, this could be a nice alternative.

Finally, it's the time of year for flowering of robin's plantain, a small, spring flowering aster.  I only recently learned of this plant, but my father has successfully propagated it from collected seeds and says that it does well in moist, partly sunny locations.

Aftermath of winter

Now that spring has come, I'm resurrecting the plant blog.  Here's how my front bed, which is supposed to be a mix of natives and nonnatives, looked about a week ago.  I'd say it's a strong argument in favor of native plants.

Front bed after the winter.  The gardenias were hard hit by the cold temperatures.

The dead bushes are special varieties of gardenias that were supposed to be hardy in this zone, but they were badly damaged by the winter.  (Well, first they were gnawed on by deer.)  I'll give them a growing season to recover, but I expect they'll need to be replaced.  At this point I'm leaning toward natives that are toxic and/or thorny to deter deer.  My little tea olive tree (Osmanthus sp., not shown) also looks dead.  This felt like the coldest winter in Virginia in at least 20 years, so probably I shouldn't be surprised to lose plants that are just barely hardy in this zone.  Native plants, on the other hand, have survived here for hundreds or thousands of years, so they can handle the cold.

Nonnative bleedingheart starting to flower, and native lyreleaf sage spreading like crazy.

The Dicentra, I regret to admit, was a nonnative impulse buy from Lowe's.  In retrospect, I wish I'd waited for one of the eastern native species, D. canadensis (squirrel corn), D. cucullaria (Dutchman's breeches), or D. eximia (fringed bleedinghearts), which probably would have done fine in this location.

The low, green rosettes are lyreleaf sage, a native Salvia.  They have spread like crazy via seeds.  I had just two plants a year ago, believe it or not, and this picture is after I've already dug up some of the babies!  They're too aggressive and weedy for this location, so I will soon transplant them all to a location that needs some help with erosion control.  What shall I replace them with?

I'm pleased that my Heucheras (the purple varieties and the native green ones) are sending up new growth.  They were also eaten by deer, but you can hardly tell now.

Bluebells and heucheras.

I'm thrilled with the bluebells (Mertensia virginica).  They're so pretty, and even the one I accidentally dug up has returned this year.  Also, they must have gone to seed last spring, since in the past couple days I'm finding tiny bluebell sprouts.

Bluebells:  Delicate, ephemeral, and absolutely perfect.

I'll leave you with some pictures of other plants that are sending up leaves, a promise of good things to come.

Lobelias (L. cardinalis and L. siphilitica).  These keep their leaves and photosynthesize throughout winter, so it's important not to let them get buried by fallen leaves.  Now they have new spring growth and will soon send up flowering stalks.  [Edited to add:  The topmost and rightmost plants turn out not to be L. siphilitica, even though they were sold to me as such at a plant sale.  When they started sending out runners and then flowered, I IDed them as bugleweed (Ajuga reptans), which the VA Dept. of Conservation and Recreation lists as "occasionally invasive."  I have since removed them and replaced them with actual lobelias from yet another plant sale.]

Blue mistflower (Conoclinium coelestinium)--the little shoots, not the nonnative bulb plant.  This seems to have spread slightly via roots since last year, or else it dropped its seeds in a very localized patch.

I think that two of these are native Aruncus dioicus (goat's beard) and two are nonnative astilbe.  However, I don't recall which is which.

Spiderworts (Tradescantia sp.)

Soon to come:  I will build a border around this bed so I know how much space I have to work with.  I think that will help a lot with finalizing the design.  Maybe I'll actually finish mulching it, too.