Jump to content

Building an outside, raised bog garden.


Sue

Recommended Posts

I read the bog garden section from cover to cover (so to speak), an outdoor bog garden is something that has been on my wish list for quite a few years. Over the last week I put all my newly gathered knowledge into practice. It didn’t all go to plan but I got there in the end.

This is the raised, stone bed I was going to use, it is 1.4 meters in diameter.

1-1.jpg

I dug the soil out to a depth of twelve inches (30cm) and a further section in the centre for the water reservoir. I particularly liked the idea of less watering, my small bog needs almost daily watering. This is where I hit hick-up No.1, this was exactly where the electric cable to the garden was buried.

1a-1.jpg

No.2 hick-up was the liner, I needed 2.5m x 2.5m, the smallest I could buy off the roll was 4.5m wide or 4m x 4m ready cut, both were ridiculously expensive and very wasteful. I could have ordered it but patience isn’t one of my strong points. Tucked away in the garage was a huge bit of hole free liner, the problem with this was it was old so had become very stiff. It would just take a lot more work.

1b.jpg

Eventually with a lot of folding and growling I got it to fit. I placed an old bread basket upside down over the reservoir and covered this with capillary matting. I put a pipe in for ease of filling the reservoir.

2.jpg

Next came a breathable membrane, this would stop all the peat filling the reservoir but would let water through.

3.jpg

An inch of silica gravel.

4.jpg

It was topped up with a 50/50 mix of sphagnum moss peat and silica gravel. I trimmed the pond liner down to an inch below the surface, I’m not sure if this will be low enough yet and cut the pipe level with the soil.

5.jpg

Finally I researched the growing heights of the Sarracenias and planted them according to their height.

6.jpg

I’m not sure about adding moss, it sounds like it can get invasive.

I read it would be beneficial to mulch with pine needles over winter, is this correct? There is a plentiful supply where I walk the dog so it would be easy to do.

This is my first large bog garden, I am hoping I have it right, I welcome any comments good or bad. I would much rather remedy a problem now than wait for it to turn into a disaster later.

Link to comment
Share on other sites

Its a lovely looking bog. However, I think I can see a fundamental flaw with the system. It seems to me that the reservoir is not going to do anything, as when the water level drops slightly it will not be in contact with the bog above and so will not wick upwards. I think the medium should surround the reservoir (not sit above it) so that the water can soak into the medium even as the water level falls (hence saving you the hassle of watering). With your system you will have to add more water everytime the water level falls a few mm and breaks contact with the medium.

By the way did I say it looks great :)

Edited by mantrid
Link to comment
Share on other sites

I also like your bog. But I dont think you will find that a bog use particular less water than pots standing in a tray.

You will also soon find that you need a bigger one :)

I can recommend using living sphagnum moss. There are so many species to chose from. Some are directly invasive and grows too much in winter.

Go for those who live on the dry side and not those that lives almost submerged. Also, red ones usua behaves well as well as more white species.

Mosses are also a good indicator of a correct enviroment for the CPs as the mosses looks bad before the plants.

I can also recommend to use Droseras in your bog as ground cover. You can see some of the hardy species here: http://succulentsonice.blogspot.com/2011/07/sundews-and-garden-bogs.html

Martin

Link to comment
Share on other sites

My mistake, I forgot to say there is a large wick which goes to the bottom of the reservoir. I’m not expecting this bog to use less water, I’m hoping with the reservoir I will need to water it less often. I have a very small bog garden (large enough for four Sarracenias) this needs watering every day in the summer.

Where would I buy sphagnum moss? I did a search on the internet and have come up with loads of hits for hanging basket liners. Does the less invasive species have a name so I know what I am asking for?

I have two Droseras, they were given to me and just labelled ‘carnivorous plant’ so I’m not sure if they are hardy species or not. I need to do a little more research on them.

Link to comment
Share on other sites

Dont know how well a wick would work, depends on the material and diameter.

More efficient than a wick would be to dig six inches or so all around the basket and push the breathable membrane down into it, then fill with peat, continuous with the upper main body of peat forming the bog. This way the water will soak sideways into the peat surrrounding the basket and wick up through the peat to the bog above. The large surface area of peat in contact with the side of the water reservoir via the membrane means that the wicking effect will be more efficient.

Edited by mantrid
Link to comment
Share on other sites

Hi Sue

That looks good and the advice recieved is sound. As far as sphagnum goes, if you have a lot of pine trees close, the chances are you can find somemoss there. I have it in my bogs, it is great looking and useful, but it is a magnet to birds in spring during the nesting season, at which time it is ripped up wholesale and with it any seedlings, drosseras and small pitcher plants, leaving me fuming. If you want to buy some (which you should from a sustainable source) then there are people on well known auction sites that sell it, also florists, nurserys etc, but make sure its sphagnum, some people sell what I call sheet moss (sorry no good with moss ID) and it can be positively lethal to CPs.

As for mulching with pine needles or fern fronds or any other breathable medium, I would recommend it, as the bog isnt too wide, also to stop the desiccating winds on the plants which can kill them in the very cold weather and if your plants are new or not used to being out all year round they will need mollycoddeling for the first couple of years, so a mulch will be usefull.

The reservoir will be a godsend next year, then come summer you will probably wonder why you didnt make it bigger. but over winter you will need to keep the bog just moist if possible, to stop the bog freezing solid, so a syphon or some form of drainage may be necessary to remove excess water.

Looks good now, but it will be an absolute treat next year, best of luck

Steve

Link to comment
Share on other sites

Sue, if you write me next spring I can send you various hardy Droseras and some sphagnum moss I use. Please remind me early April.

Martin

Link to comment
Share on other sites

My mistake, I forgot to say there is a large wick which goes to the bottom of the reservoir. I’m not expecting this bog to use less water, I’m hoping with the reservoir I will need to water it less often. I have a very small bog garden (large enough for four Sarracenias) this needs watering every day in the summer.

I've used the 'self watering' plant pots for seveal years with the same idea of the wick as you describe, it works fine.

Link to comment
Share on other sites

Dont know how well a wick would work, depends on the material and diameter.

More efficient than a wick would be to dig six inches or so all around the basket and push the breathable membrane down into it, then fill with peat, continuous with the upper main body of peat forming the bog. This way the water will soak sideways into the peat surrrounding the basket and wick up through the peat to the bog above. The large surface area of peat in contact with the side of the water reservoir via the membrane means that the wicking effect will be more efficient.

That makes a lot of sense. The method I have used is the same as I use in my greenhouse, it works well in there although my plants need to be kept damp and not wet (non CPs). I will see how well it performs next summer, to change it at this stage would take a lot of work.

Hi Sue

That looks good and the advice recieved is sound. As far as sphagnum goes, if you have a lot of pine trees close, the chances are you can find somemoss there. I have it in my bogs, it is great looking and useful, but it is a magnet to birds in spring during the nesting season, at which time it is ripped up wholesale and with it any seedlings, drosseras and small pitcher plants, leaving me fuming. If you want to buy some (which you should from a sustainable source) then there are people on well known auction sites that sell it, also florists, nurserys etc, but make sure its sphagnum, some people sell what I call sheet moss (sorry no good with moss ID) and it can be positively lethal to CPs.

As for mulching with pine needles or fern fronds or any other breathable medium, I would recommend it, as the bog isnt too wide, also to stop the desiccating winds on the plants which can kill them in the very cold weather and if your plants are new or not used to being out all year round they will need mollycoddeling for the first couple of years, so a mulch will be usefull.

The reservoir will be a godsend next year, then come summer you will probably wonder why you didnt make it bigger. but over winter you will need to keep the bog just moist if possible, to stop the bog freezing solid, so a syphon or some form of drainage may be necessary to remove excess water.

Looks good now, but it will be an absolute treat next year, best of luck

Steve

Firstly, I love your user name and even more your Avatar. tsl_wub.gif

Today I gathered some mosses (my brother, as part of his job, was clearing a pine forest), so I rescued some, they look great but I’m not sure they will cope with full sun come the summer. I do have an orchid nursery just up the road so the kind of sphagnum moss they use will be easy to get.

I read in the bog garden thread about keeping the soil moist, not wet during winter. The bed was an existing bed so I couldn’t work out a method of draining it. I’m now working on the premise that a good, thick mulch will rectify the situation (it is probably the same theory the Emu had when it buried its head in the sand!).

Sue, if you write me next spring I can send you various hardy Droseras and some sphagnum moss I use. Please remind me early April.

Martin

Hi Martin

That is a very kind offer, you may very well hear from me in April.

Link to comment
Share on other sites

My bog garden is for the main part often submerged. After rain the rhizomes of half of the plants have at least 2 - 5 cm of water above them. This works well. A naturalized sarracenia population near by has as much as 10 cm above the rhizomes during winter and they are thriving.

Martin

Link to comment
Share on other sites

My bog garden is for the main part often submerged. After rain the rhizomes of half of the plants have at least 2 - 5 cm of water above them. This works well. A naturalized sarracenia population near by has as much as 10 cm above the rhizomes during winter and they are thriving.

Martin

Thank you Martin, that is reassuring. I have the liner one inch below the soil surface so they should never sit in water or be submerged. I should be able to siphon off water using the pipe for filling the reservoir. It may be possible to fold the liner down more during the winter, I will wait until we have some heavy rain to see if this is necessary.

Link to comment
Share on other sites

Hi Sue

I would definitely try to keep the water level lower rather than higher, as you bog is raised and has a relitevly small mass it will cool down and warm up a lot quicker than one at ground level which has a large mass around it to give it some thermal inertia. The more even you can keep teh peaks in temperature the better I think

Firstly, I love your user name and even more your Avatar. Thanks for that, it is the bike I ride.

Sorry to hijack a bit here but Megs what sort of temperatures do you get down to in Denmark? I think it must be lower than ours in the UK, do you have any experience leaving plants other than purpurea out all winter?.

Cheers

Steve

Link to comment
Share on other sites

I was going to write a thread about it but heres the short ansver.

I only cultivate CPs outside except for a few mexican Pings and my N. argentii, so I need hardy material.

As you have already imagined I have lots of purpureas, I collect them as they are my favorite Cper.

Besides that hybrids with Sp, flava forms from Florida to NC and Virginia, all are hardy, oreophila forms, and many kinds of hybrids.

besides that all temperate forms of Droseras, even D arcturi survived lasts winters - 23C!

And various Pings.

I dont have pure forms of leucophylla, minor or psittacina but have them represented as hybrids. Its not warm enough during our summer for them to grow.

Earlier I had them in unheated greenhouses but that wa s in my old house. I went from 150 sqamteer of greenhouse to 9,9 sqm....

Martin

Link to comment
Share on other sites

  • 2 months later...

Thanks Kiwi, I’m hoping the bog will come into its own next year, I’ve found with other plants I grow that once the restriction of a pot has been removed, they grow larger and stronger.

The bog has remained constantly damp, even with high rainfall it has not become waterlogged. I gathered a couple of sacks of pine needles to mulch the bed if the weather turns very cold.

The Sarracenias and the fly traps are doing very well with some of them still growing. The Drosera are not doing so well, this is the first time I have tried to grow these so I’m not sure if they are naturally dying back or are not happy.

Link to comment
Share on other sites

Hi Sue

If they are native Drosera, Capensis or Binata they will make it through the winter and should all be black or blackening and retreated to ground level to hibernacula in the case of natives or to their roots in the case of the others, very untidy and looks messy but perfectly normal.

Cheers and happy new year.

Steve

  • Like 1
Link to comment
Share on other sites

  • 2 months later...

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.

×
×
  • Create New...