New To Bog Gardening

9 years ago

Hello Folks. I've got a small patch (approx. 8'x10') that is wet about half of the year. I've built a ramp that runs around this spot and leads up my steep hill. The base is solid shale. I'm putting in a bog garden that will eventually be about 3' deep. This will be full of very wet soil, with no open water, save for a small pan I hope to encourage tadpoles in.

I know I need a pond liner to retain the moisture. I've read that the liner needs to have several holes poked into it, to encourage an exchange of water with the underlying surface, I suspect.

My question is do I really need to poke the holes, or just put the liner in as is? Seeing as these liners aren't cheap, it would be a shame to err on this. Also, I've got a lot of landfill compost ready to add. Should I supplement anything else like peat, sand, lime? I do not have any decent native soil at all as I sit on a mountain of shale bedrock.

I'm really excited about attempting to grow wet plants for the first time ever. Any advice is welcome!

Comments (2)

cooperdr_gw
9 years ago
Well instead of poking holes you'd either have to get some kind of pump with a really complicated filtering system or just have an overflow somewhere. Can't stop the rain. Otherwise everything would just turn to mud.
terrestrial_man
9 years ago
I think you need to explain exactly the nature of the site that you are wanting to build the bog garden in. You are saying that it is entirely bedrock of shale? You mean that you have a hole that is in solid rock?
Why would you need a liner if you have solid rock?
As far as bog substrate is concerned, compost is NOT what you should
use for any bog garden. What is needed is river sand and peat moss mixed at a 50 50 ratio. However the body of the bog in which the substrate sits should not be the entire 3 foot depth.
The bog should be built as a stratified system. This consists of various layers and an outflow, both an insert and surface flow flooding relief.
The bottom layer should be of coarse rocks into which a pvc pipe, which is large enough in diameter to take a hose for pumping water out with a water pump if necessary, is set so that water can drain freely up the pipe, this can be done using a portion of a perforated pipe or just drilling large holes in the pipe. The top of pipe must extend above the surface of the bog and can be capped with an elbow joint for controlling direction of drainage.
Upon the layer of coarse rocks should be sat a couple of layers of reticulated foam filter material-click to see with one layer ran in one direction and the upper layer ran perpendicular to the lower level. These will allow for water to flow into the coarse rocks layer and keep most of the silt, sand, and other debris out of the coarse rock layer. Upon this I would cover with a layer of coarse river gravel and coarse rocks to keep the foam from floating.
Then a layer of about a foot and a half of a sand and peat moss mix packed in tight to the area. This will be the basic growing area of the bog.
For bog plants do not crowd and avoid using any grasses, sedges, or woody perennials that can overwhelm the bog. I am presuming you are planning on growing carnivorous plants. Start with a few and give them plenty of space between plants. Put the larger species in the back or center of the bog and the smaller ones near the edges.
Before planting flood the bog and see how the water moves out so you can find what portion of the bog naturally drains. It is this area that you may want to add a few flat stones or small boulders sitting into the bog from the edge of the bog to help minimize loss of bog substrate. You might even put the container for the tapoles in this area.
I hope that this info will be of help.