How much water in a bog garden?

[Rob-Rah]

I am making a bog garden in a half-barrel for CPs and some orchids. It has been filled up with the mix I am using, and I thought that there would be enough water escaping between the slats to acheieve a good moisture balance. However, what I didn't count for was that wood expands when wet. The slats are all now firmly packed together and I have a soggy mess in the barrel - more of a thick slurry than anything I can plant into.

Anyway, I am going to drill a small drainage hole or two into the barrel (possibly the size that can be blocked up with a test-tube rubber bung if needed). Specifically I am wondering how far beneath the surface people think it would be prudent to place them. The barrel is about 18" deep I guess. The lower down they are, the less stangant the pot can get, but the higher they are the better the barrel at retaining moisture. Do potted bog gardens suffer from stagnation?

(The compromise would be to place drainage holes right at the bottom and block the holes with bungs, and then release the bungs when the bog is in danger of flooding excessivley, replacing them again when the rain stops, but this may require more careful monitoring than is really desirable)

Cheers.

[beercanoo]

i have placed the holes in the bog 3-4 inches form the top, this allows the roots to touch the water and one can make dips and hills to alternate the conditions to a plants preference(with VFT in mind aswell) i dont know about stagnent but when i left it un-holed(so to speak) the bog filled up dramatily with the recent wet weather, the plan was to allow it to get filled but i didnt count on my plant salmost drowining(my darlingtonia went very old looking-withered)... then the following heat brought upon some algae and some gold sporie stuff which grew rapidly, keeping it semi-moist with holes three inches deep also allows one to grow a nice layer of moss ....