Sign in to follow this  
Nepenthes Nut

Water Levels?

Recommended Posts

After some discussion and hard thinking I think I have the perfect system to allow me to be away from my CPs without them all dying. Now all I need to figure out is how far below the surface should the water table be? I realise that you want it moist but not soaking so what levels do you guys normally keep your bogs at and at what level do you place your overflow pipe so it doesn't flood?

Thanks,

Andrew

Share this post


Link to post
Share on other sites
After some discussion and hard thinking I think I have the perfect system to allow me to be away from my CPs without them all dying. Now all I need to figure out is how far below the surface should the water table be? I realise that you want it moist but not soaking so what levels do you guys normally keep your bogs at and at what level do you place your overflow pipe so it doesn't flood?

Thanks,

Andrew

Dont have a bog garden myself. But different plants are different sizes and with different length roots, but your water level is going to be the same throughout the bog. So what is generally done is to landscape your bog with high parts and low parts, this will provide a variety of regions of different saturations. Its then a case of putting the plants in a region where they prefer, by trial and error or asking people who have already done it.

If this was my project, and I regret not having the space to try, I would have the water table two thirds the way up. I would then landscape the peat or what ever you are using from water level to maybe a foot to a foot and a half above the water (depending on your bog size). The raised region would form a semicircle around the patch at water level. I would then plant accordingly after researching what like really wet and what likes not so wet.

Share this post


Link to post
Share on other sites

A good suggestion indeed. I am not sure however if there will be enough to have different levels, especially if the rain evens it out covering plants... but I will keep it in mind. I assume that sarras prefer drier rhizomes while drosera like it wetter?

This is just part of my research into what growers find to be the best levels, even if it is just the height of the pots you use for a tray method... Any advice would be helpful. I will also look in some reference books...

Thanks again mantrid for being the first but hopefully not last person to answer my queries...

Share this post


Link to post
Share on other sites
A good suggestion indeed. I am not sure however if there will be enough to have different levels, especially if the rain evens it out covering plants... but I will keep it in mind. I assume that sarras prefer drier rhizomes while drosera like it wetter?

This is just part of my research into what growers find to be the best levels, even if it is just the height of the pots you use for a tray method... Any advice would be helpful. I will also look in some reference books...

Thanks again mantrid for being the first but hopefully not last person to answer my queries...

The rain problem would be over come my using some form of barrier, eg rocks etc. Personally I would use bog wood, a kind of preserved wood dug out of bogs, looks great. You could probably use normal logs, I think they would not break down sufficiently/quickly enough to upset the balance of pH or nutrients in the bog. But I'm not sure on this you would have to research a bit more.

Share this post


Link to post
Share on other sites

Does anyone have any measurements of their overflow pipe's level below the soil level or the average water level in their bogs?

Share this post


Link to post
Share on other sites

Surely someone has a bog with an overflow pipe at least? All advice on minimum and maximum ranges of water levels would be great so I can get it right first time, especially with the overflow pipe, don't want to have to drill more than one hole...

Share this post


Link to post
Share on other sites

Hello,

I have a small bog, but my technique could be applied to a bigger one as well.

I have a overflow pipe. And a water level measure pipe.

I have made some photos:

Here you see the overflow pipe:

moeras_9.jpg

And here the water level measure pipe and the overflow pipe.

moeras_10.jpg

The water level stays 10-15 cm below the soil level at least. In summer it could go to 40 cm below soil level, but usually I fill the bog with new water true the vertical pipe.

At the bottom of my bog I have a water reservoir.:

moeras_6.jpg

More pictures can be find here:

http://vleeseters.nl/fotomoeras.php

Share this post


Link to post
Share on other sites

Great pictures and a very interesting method of combining an overflow and a water level gauge. I have a system that will hopefully keep the water level at a constant level so I will arrange it to be about 15-25 cm below the surface and an overflow at 10 cm. How does that sound?

Share this post


Link to post
Share on other sites

Sounds good for me. But how do you want to make sure the water level will be at a constant level?

An other thing you should know: Don't plant your plants in right after you finished your bog. Wait a few months. The soil will collapse, so you have to ad some more after a few months.

Share this post


Link to post
Share on other sites

I have a huge old butler's sink as a bog (empty, two strong men could just about lift it with the definite risk of a hernia). I don't worry too much about water level other than to top it up if it is starting to look dry; I don't have an automatic system so cannot help you decide an ideal water level, sorry.

I do allow very slight seepage through the plug hole at the bottom and, now and again (no more than annually) flush out all the water through this plug hole; the idea to get rid of toxins.

I have an overflow at or just below (5cm) peat surface (peat surface is about 10cm below sphagnum surface). If you can put some hysteresis in the water level filling mechanism then that would be great as it will allow a bit of oxygenation and, for an open bog, I would make the range e.g. 0-15cm relative to peat surface i.e. fill up until peat surface reached, then don't fill again until drops to 15cm.

Edited by jimfoxy

Share this post


Link to post
Share on other sites

I have three "mini bogs" made from large plastic containers..

each one has a drainage tube located about 3" (about 8 cm) down from the surface..

water level doesnt get higher, but it can get lower as water evaporates..

(I dont have any way to monitor the water level..I dont consider it terribly important..

I simply add water if its been awhile without any rain, until water comes out the drainage tube..)

This is the third year with this setup..seems to be working fine.

CP2008-058.jpg

CP2008-062.jpg

CP2008-017.jpg

CP2008-047.jpg

Scot

Edited by scottychaos

Share this post


Link to post
Share on other sites

Thank you for all your replies. It certainly has given me food for thought.

Jimfoxy, I am not sure if I plan to have a sphagnum topping to the bog as of yet and certainly do not know how I could automate the fluctuations in water level. I could possibly get a valve with a timer to allow watering every other day up to the set level to allow some fluctuation.

MarcelvW, I will probably have to plant it when I finish it as I will be taking my plants bare rooted from their current home in Paris to Cambridge. I will however water it in thoroughly to try to ensure maximum settling before I plant to minimize collapse. I will be using a header tank, like in tap water systems in the roof. It is basically just a ballcock valve in a tub. Something like this Then connecting that to the water butt and the bog via hose pipe. I plan to feed the hose pipe through the overflow pipe so as to hide it. The overflow being wider than the hose pipe and sponge place around it to prevent soil loss.

From the sounds of things, a water level around 25 cm below and an over flow around 10 cm below the top. If I added a sphagnum top dressing, it would only be 1cm thick, to begin with at least, so this shouldn't affect the positioning of an overflow really. The overflow was the more important thing to get right as it is much harder to alter if you get it wrong the first time. Water level can be changed by just raising or lowering the water tank.

I hope to post pictures of the step by step construction when I get back next week and assemble it all (bought all the components last week while I was over)

Edited by Nepenthes Nut

Share this post


Link to post
Share on other sites

Glad to hear you are making progress with your bog, I enjoy reading this type of post. Below I have picked up on a few things I would do different, however, please feel free to ignore if you dont agree after all I'm no expert.

Jimfoxy, I am not sure if I plan to have a sphagnum topping to the bog as of yet and certainly do not know how I could automate the fluctuations in water level. I could possibly get a valve with a timer to allow watering every other day up to the set level to allow some fluctuation.

This would not be neccessary with your ball valve as this will be regulating the water hight automatically keeping it at the exact level you set it at. I woulddnt wast any money on uneccessary technology, simplicity is best.

I plan to feed the hose pipe through the overflow pipe so as to hide it. The overflow being wider than the hose pipe and sponge place around it to prevent soil loss.

I think I would use some sort of aquarium type filter wool or garden fleece as the pores in a sponge would quickly block with peat and gunk.

From the sounds of things, a water level around 25 cm below and an over flow around 10 cm below the top.

Remember that this will mean your water level in the bog will fluctuate over a range of 15cm, depending on the weather, maybe this isnt a bad thing. Personally I would put them at the same height to keep the water height constant and adjust the substrate level to fine tune where it is in relation to the plant roots. Another thing to bare in mind is that if it rains and the water level in the bog is at the 10cm overflow level so is the level in the tank, and as your ball is set to close the valve at 25cm this would mean the ball is 15cm under water and trying to bob to the surface putting excess force on the arm and valve this could shorten the valve life but more likely gradually bend the arm and change your setting of 25cm to less.

The overflow was the more important thing to get right as it is much harder to alter if you get it wrong the first time. Water level can be changed by just raising or lowering the water tank.

You will find your ball is adjustable, usually it can slide up and down the arm and fixed in a particular position with a screw, or if it is a metal arm it is common practice to adjust the ball position by bending the arm. Much easier than digging up the tank.

As I mentioned Im no expert, but I have done similar things for linking aquariums together and keeping water levels at certain positions in each. Look forward to your pics.

Edited by mantrid

Share this post


Link to post
Share on other sites

I do not think it matters if the sponge gets blocked with peat as it is still permeable to water.

The pipe would not transmit the water back to the tank I do not believe as the pipe will enter higher than the water level and drop down. If I inserted the pipe from the bottom then this would indeed be the case.

Yes, the ball is indeed adjustable but thats over a small range so would be used for fine tuning.

The rest of it I will take on board, Thank you.

Share this post


Link to post
Share on other sites
The pipe would not transmit the water back to the tank I do not believe as the pipe will enter higher than the water level and drop down. If I inserted the pipe from the bottom then this would indeed be the case.

Perhaps I am misunderstanding what you are doing. But from what I can see the water has to be able to get back to the tank in order for the ball valve to regulate the bog water level. My understanding is that if the water outlet of the tank is higher than the bog it will just pour out continuously as there is no back pressure of water ie water staying in the tank, to raise the ball and cut off the valve. Later I will do a little diagram to try and explain how I would tackle this which will help explain what I mean.

Below

bogsystem.jpg

Edited by mantrid

Share this post


Link to post
Share on other sites

This diagram entails that the connection pipe is lower then the water level. I was planning on having the pipe come from above the water level and then drop below, acting more like a siphon than a direct link that will stop when the pressures in the bog equal that of the tank. Thinking a little harder, I am not sure if my original idea would work... I will get back to you in tomorrow with a better thought out plan.

Share this post


Link to post
Share on other sites
This diagram entails that the connection pipe is lower then the water level. I was planning on having the pipe come from above the water level and then drop below, acting more like a siphon than a direct link that will stop when the pressures in the bog equal that of the tank. Thinking a little harder, I am not sure if my original idea would work... I will get back to you in tomorrow with a better thought out plan.

Still cant see it. I dont think the bog can exert a pressure as it is open. If I understand what you are proposing then from what I can see the water will just pour out continuously and then when it fills the bog out through the overflow until the butt is empty. Would you be able to do a diagram this would clarify what you are going to do. I used 'paint' under accessories in Windows.

Share this post


Link to post
Share on other sites
Still cant see it. I dont think the bog can exert a pressure as it is open. If I understand what you are proposing then from what I can see the water will just pour out continuously and then when it fills the bog out through the overflow until the butt is empty. Would you be able to do a diagram this would clarify what you are going to do. I used 'paint' under accessories in Windows.

I do see what you mean by that yes... I am just wondering whether or not when the water level reaches that of the tank, the pressure of the water in the bog will equal that of the tank and will prevent any more flowing, as it would in your system... I am afraid I do not have MS paint and no programs to easily draw a diagram. I will consult someone on this problem you have highlighted, thank you.

Share this post


Link to post
Share on other sites

I read your messages again. Do you mean like this.

bogsystem2.jpg

Share this post


Link to post
Share on other sites

If so I think this would also work. Thinking about it in practice the only thing I can see that may cause a problem is gas being produced by the organisms in the bog such as methane and see hoo too. These gases would rise to surface as bubbles. Some would enter your siphon tube accumulating at the top and forming an air lock. This would eventually break the water link between tank and bog. How often this would happen is anyones guess but I think it would be more common in summer when biological activity is higher.

Share this post


Link to post
Share on other sites
If so I think this would also work. Thinking about it in practice the only thing I can see that may cause a problem is gas being produced by the organisms in the bog such as methane and see hoo too. These gases would rise to surface as bubbles. Some would enter your siphon tube accumulating at the top and forming an air lock. This would eventually break the water link between tank and bog. How often this would happen is anyones guess but I think it would be more common in summer when biological activity is higher.

Yes. That is basically what I meant but from thinking about it, the siphon would work both ways so an overflow higher than the water level would put stress on the valve when it rains. There is also one other factor that could break the siphon and that is the water level dropping below the end of the siphon tube if say the water butt ran dry. The only way around both would, in my mind, be to put a pipe (with holes in the sides) in vertically and feed the hose into that such that fewer micro organisms to make bubbles and the end of the pipe would be in actual water, not just the peat as im not sure how well a siphon works in a porous medium. This would also allow me to monitor the water level. It would be a little like MarcelW's set up but it would have water fed into it.

Or, some once can tell me of a good way to seal a pipe into the bog so that is it water tight. It is either risk the siphon stopping and it cant restart, or risk a leak.. they both end the same if not caught in time but I think the siphon is easier to restart...

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this