Can Wicking Beds be used to mediate wet areas?

First off, sorry if this is the wrong place to post this. New hear, lots of forums, gotta learn where things go. ; )

So, we're building a new home in the middle of 60 acres of woods in central Pennsylvania. We've built the house on the side of a fairly gentle slope. Near the top, and for most of the slope near the house, the ground is reasonably try most of the year. As you get to the back of the house, the slope gets much gentler, but continues on down toward the stream and tends to be quite wet more often than not, and downright swampy at times.

We've got ~2 ft of okay topsoil (depending on where you dig) and then you hit dense gray clay. As you go uphill it's full of great big chunks of sandstone, absolutely everywhere. As you get to the gentler slope closer to the screen the rocks stop, it's just all dirt & clay. The stream itself seems decently fresh for this area -- I haven't tested it, but it's clearer & sweeter than most of the water around here (almost all of which runs through an old mine at some point).

I'm excited about the plentiful moisture, compared to the fairly dry hilltop field we live on now, but all my gardening experience so far is keeping plants from drying out, not keeping them from getting to wet!

Did a lot of reading (much of it on these forums) looking for ideas, and wicking beds caught my eye. Could a wicking bed (with no bottom barrier) be used to take advantage of all that water without over-soaking plants? The process I imagine is:
- dig a trench down to that clay
- add a layer of gravel (with the pipe running through)
- frame the bed around it
- add the topsoil (mix in some nicer soil we have) back in on top of the gravel

I'm assuming this would wick up all the water running along that clay, but still keep the plants toes up out of it. Is that a feasible plan? Or am I missing something that won't let it behave as I'm imagining.

And if I still have the watering pipe running down and through the gravel, would I be able to use that to gage the water level as well as still add water during dry times?

Thanks for your help.
- Cody

A key to water killing plant roots is the available oxygen.
What tends to happen is anaerobic conditions develop and the plant roots die from lack of oxygen.
You will likely find that you need raised beds or hill rows.
These will allow your plant roots to get oxygen and provide a place for water to drain.
So when you look to planning your garden look at drainage first.
You may wish to dig some holes and fill with water to measure soil drainage in different areas.
In some cases people have done perk tests using dye to see how ground water flows.
My concern with all the clay is that it could create a perched aquifer. Meaning you could have water close to the surface during your wet season.
First thing I would do is go online and see if your county has a soil survey.
It may be that the soil types for your property are already mapped and you can start your planning with that soil map.

Alex,

Thanks for the tip about the Soil survey. I did indeed find information for our property. The area around the home site is listed as "Hazleton-Clymer channery loams, 3 to 8 percent slopes". The depth to water tabe rating is listed as ">200cm". On some areas it's listed at 51cm, but those are not near the home. I'm not sure if that's the relevant information? It will take me bit of learning to parse this all.

We did have a perc test done when we were trying to get a septic system approved. I don't know the details of the results, but I know we were given "credit" for 2 feet of good drainage - meaning we still had to build a sand mound, but that it could be 2 ft shorter than would have otherwise been required.

When we were looking for a good spot to do that perc test we dug several 6 ft holes. They filled up on their own (without rain) in a day or two. Some drained after a span of dryer weather, some were still very wet when we filled them back in.

I'm familiar with raised beds, but not hill rows. Is that literally a row on the side of a hill? Or are those "mounded up" rows? Searches on the term mostly lead to me article on raised beds.

I am interested in building raised beds, as you suggest, to keep roots up to improve drainage. I was wondering if gravel (between the soil in the raised bed, and the clay in the ground) similar to a wicking bed design would help create a favorable situation, or if this is not the appropriate place for that.

Hi Cody,

Read up on hugelkulture, there is a complete forum to peruse. In my current home, I have inches of topsoil and then total clay. I started with raised beds of about 10" prior to finding huglekulture which helped the drainage issues. Whenever it rains, even just a bit, my backyard is ankle deep in water. The raised beds helped to keep the plants from drowning but in dry times, I had to water like crazy. I changed over a few of my beds into a modified huglekulture type bed as an experiment to find out if I could not only keep them dry but, would they take care of watering themselves also. I have to tell you, huglekulture is definitely the way to go for me and I think it would work great in your area also.

In traditional huglekulture, you pile up lots of wood such as logs in a pile about 6 foot high, cover with a bit of soil or compost and plant. As the wood begins to rot, water is absorbed and you no longer have to water the beds. My very small yard would have only allowed me maybe 2 beds so I did a modified version. It probably is not as good as the traditional one but it works out great for what I need. My beds were already 10" deep soil filled beds lined with weedblock. I dug out the soil and cut away the weedblock. I then filled them heaping with all the wood chips I could get and then put most of the soil back on top. The plants are thriving and I no longer have to water (well this year has been wetter than normal at the beginning but in times like this I still had to water if no rain in 2 days, this year NOT).

Anyway, take a look at the hugelkulture forum, I really think this is what may work for your situation. Kim

When I say hills I am thinking potato hills.
I have a old tiller with a potato hiller.
If you take a topographic map you can see the lines as elevation changes.
From what you say you have not much of a slope.
Base on the holes filling up I bet you have a perched aquifer. Meaning surface water hits clay or poor drainage not too deep so water travels underground close to the surface.
If you till along the Key lines, think elevation lines on your topographic map, can use a potato hiller to make dips and hills.
The dips trap water but should still drain over time. The hills keep the roots out of the water.
In dry areas they use a deep blade to open the ground and allow water to enter.
In wet areas direct water away without eroding soil.
If you are ambitious you can dig and bury the wood and logs as discussed above.
This also creates a area to trap water and provides a space for roots to grow out of the water.
Finally, you can look at drain tiles and such to direct ground water. Provide drainage and roots do not die.

Here is a cheap trick to see how you soil is doing.
Get some iron rods and drive them into your soil.
Pull them out after a season.
Rust mean you have oxygen, black means you had rust OXYGEN than went anorobic NO OXYGEN, clean mean never had oxygen.

alex Keenan wrote:When I say hills I am thinking potato hills.


Here is a cheap trick to see how you soil is doing.
Get some iron rods and drive them into your soil.
Pull them out after a season.
Rust mean you have oxygen, black means you had rust OXYGEN than went anorobic NO OXYGEN, clean mean never had oxygen.

Thanks for the tip - wanting to try this on my place!
The gray clay is an indicator of periods of waterlogging where roots just won't thrive. If yours are at 2 ft, you probably need to raise the soil level for many plantings. I usually do local drainage digging and pile the spoils, then plant about 1/3 up the spoils pile (which will shrink over time..)