Potential pond

[treecreeper]

I cleared a fallen rhododendron in the garden and dug out all the roots. I am left with a piece of ground (pictured below) which I would like to turn into an amphibian pond, primarily for frogs and toads. I'll definitely need a liner as the soil gives way to pure sand at a foot's depth but I can't decide on the construction. I have DIY books and also The Wildlife Pond Handbook by Louise Bardsley. Both recommend a shallow zone with a deep zone in the middle but they have different ideas about the edge. The DIY books have the edge steep with overhanging edging stones to protect the exposed liner from the sun. Miss Bardsley's scheme is more complicated, with the entire liner buried and the edge sloping gradually to create a wet to dry transition.
I can see the superiority of Miss Bardsley's plan - not least because it allows the newly metamorphosed anurans to exit the pond - but I suspect it needs a lot more space than I've got, which is something like a quarter circle of ten feet radius.
All comments welcome. I'd also appreciate advice on pond liners. According to Miss Bardsley EDPM rubber is best, followed by Butyl.
Photos (shed is 8 x 6 feet):

[Tursiops2]

Hi treecreeper.

That looks a good spot for a pond - sunny and sheltered. As for edging; generally, the more of the "transitional" edge the better, as this increases the planting area and diversity of conditions. It is a good idea, though, to have an area of hard-standing along one edge of the pond to provide non-slip access for maintenance etc.

You may find my diagrams in this thread helpful, you could certainly adapt that layout and structure to your circumstances (page 3): wildlife haven in the shade?

T2

[diggleken]

Hi treecreeper,
I've used builders thick plastic and a proper butyl liner in the past, both have been OK for years, but Butyl is prob best, just make sure you line the bottom with cardboard, sand etc so no jagged edges -water gets very heavy.
have a deepish bit to avoid freezing through (12'' to 15''), plus shallow too - both will suit different waterlife.
Make sure you have a climbeable out escape route for critters that fall in besides the emergent froglets etc.
I also like to bung in lots of smelly mud from good local ponds - its great fun watching what happens and what colonises!
I would say just make it as you feel, but cover the edges for a more natural look with stone - you will probably do it again in a couple of years anyway I suspect!
Cheers
Ken

[treecreeper]

Thanks for these contributions. T2, I've just been admiring your detailed drawings on the link. The great benefit of your design is its versatility. As you say, the pond doesn't have to have radial symmetry with a uniform shallow shelf all the way round. I can see the benefit (not least in saved space) of a steep drop against the wall and the shed and a shallow slope towards the lawn and the bushes. This also addresses your concerns about things falling in, Diggleken. We get a lot of hedgehogs in the garden.
Soon I'll be digging....

[Tursiops2]

Originally Posted by treecreeper

I can see the benefit (not least in saved space) of a steep drop against the wall and the shed and a shallow slope towards the lawn and the bushes.

Actually, I'd do precisely the reverse . Why? Well...

1.You won't be able to run the pond right up to the wall, for construction reasons, so you will need to set it in from the wall.

2. A south-facing brick wall is an asset in a garden - it reflects light and heat back into the garden, and what it doesn't reflect, it absorbs and releases during the night. They're great for planting climbers up, and planting along the foot. You'll need space for access, a couple of feet at least.

Grow Ivy up that wall and it will be a wildlife haven in its own right, and planting along the foot of the wall will reflect in the pond and look much better than a sheer vertical drop.

3. Ideally, the planted "shore" of a wildlife pond should grade into an undisturbed area of vegetation, not a well-trodden lawn, so grade the shore up to the wall.

4. The void under the shed will provide shelter for amphibs - give them cover on the way there by grading the shore up to the shed (allowing 10cm+ for the overlap of course).

5. It's desirable, for safety reasons, to have a well-defined transition from lawn to pond, and easy access for maintenance, so place your paving along the lawn edge where it serves both functions.


Hope that helps
T2

[treecreeper]

Originally Posted by Tursiops2

Actually, I'd do precisely the reverse . Why? Well...

1.You won't be able to run the pond right up to the wall, for construction reasons, so you will need to set it in from the wall.

2. A south-facing brick wall is an asset in a garden - it reflects light and heat back into the garden, and what it doesn't reflect, it absorbs and releases during the night. They're great for planting climbers up, and planting along the foot. You'll need space for access, a couple of feet at least.

Grow Ivy up that wall and it will be a wildlife haven in its own right, and planting along the foot of the wall will reflect in the pond and look much better than a sheer vertical drop.

3. Ideally, the planted "shore" of a wildlife pond should grade into an undisturbed area of vegetation, not a well-trodden lawn, so grade the shore up to the wall.

4. The void under the shed will provide shelter for amphibs - give them cover on the way there by grading the shore up to the shed (allowing 10cm+ for the overlap of course).

5. It's desirable, for safety reasons, to have a well-defined transition from lawn to pond, and easy access for maintenance, so place your paving along the lawn edge where it serves both functions.


Hope that helps
T2

Yes, that makes much more sense. I like the ivy idea, I hadn't thought of using that wall. I'm not quite clear about item 4 though. Do you mean the edge under the shed should have the same slope as the perpendicular edge by the wall? Or are you suggesting I should undermine those flagstones a bit?

[Tursiops2]

Ok, referring to the photos, what I'm visualising is a rectangular excavation (say, 2m along the shed, 2.5m-3m along the wall, set in from the wall about 60cm.This will require cutting out a bit more of your lawn to get the shape), with the sides contoured to create deeper water in the near corner, the wall and shed sides graded, and planting along both these edges.

The effect is to create a (roughly) quarter-circular pool, with it's radial centre at the corner nearest the observer, enclosed on the two far sides by shore.

Don't undermine the flags, or try to run the liner under them. Just allow 10cm out from them for the liner, and turf this strip with the turf you'll dig up from the lawn. The strip of exposed flags isn't wide enough to be a significant problem to amphibs.

Does that make sense?
T2

[treecreeper]

Originally Posted by Tursiops2

Ok, referring to the photos, what I'm visualising is a rectangular excavation (say, 2m along the shed, 2.5m-3m along the wall, set in from the wall about 60cm.This will require cutting out a bit more of your lawn to get the shape), with the sides contoured to create deeper water in the near corner, the wall and shed sides graded, and planting along both these edges.

The effect is to create a (roughly) quarter-circular pool, with it's radial centre at the corner nearest the observer, enclosed on the two far sides by shore.

Don't undermine the flags, or try to run the liner under them. Just allow 10cm out from them for the liner, and turf this strip with the turf you'll dig up from the lawn. The strip of exposed flags isn't wide enough to be a significant problem to amphibs.

Does that make sense?
T2

Got it now, you're moving the centre of the quadrant diametrically opposite to where it is now (i.e. it will now be opposite to where the shed intersects the wall), with paving alongside the lawn (a bit more of which is sacrificed towards the new centre - no problem) and the bushy bit opposite the shed.
I have a question about the paving. I want the pond to look as natural as possible and not like a B&Q project. Instead of paving stones could I use something like metal grids, the sort you get outside doors for allowing people to scrape the mud off their boots? Or some sort of paving stone with holes? What I have in mind is something you can stand on and that protects the lining, but becomes hidden by grass and weeds growing through it.

[Tursiops2]

Originally Posted by treecreeper

Got it now, you're moving the centre of the quadrant diametrically opposite to where it is now (i.e. it will now be opposite to where the shed intersects the wall), with paving alongside the lawn (a bit more of which is sacrificed towards the new centre - no problem) and the bushy bit opposite the shed.

Yes, that's it

Originally Posted by treecreeper

I have a question about the paving. I want the pond to look as natural as possible and not like a B&Q project. Instead of paving stones could I use something like metal grids, the sort you get outside doors for allowing people to scrape the mud off their boots? Or some sort of paving stone with holes? What I have in mind is something you can stand on and that protects the lining, but becomes hidden by grass and weeds growing through it.

That's a very good question. I've never seen it done, but it seems do-able. But, although I can see where you're coming from, I don't like the idea. Part of the reason for having hard-standing is to provide a stable and non-slip surface, rather than grass which can be slippery when wet. I'm not sure your suggestion would achieve this. Do you have kids?

If you want a "softer" more natural look, you could use decking rather than paving - I believe you can get slab-sized decking panels for this purpose- and plant beneath the tree (Holly?), bringing it forward along the (West?) end of the pond. Don't pave this edge, turf it.

T2

[treecreeper]

Originally Posted by Tursiops2

That's a very good question. I've never seen it done, but it seems do-able. But, although I can see where you're coming from, I don't like the idea. Part of the reason for having hard-standing is to provide a stable and non-slip surface, rather than grass which can be slippery when wet. I'm not sure your suggestion would achieve this. Do you have kids?

If you want a "softer" more natural look, you could use decking rather than paving - I believe you can get slab-sized decking panels for this purpose- and plant beneath the tree (Holly?), bringing it forward along the (West?) end of the pond. Don't pave this edge, turf it.

T2

The kids have grown up now so there's no safety problem. Despite my sneering reference to B&Q I'll see what they have in decking next time I go there The tree is laurel, by the way. It does look a bit hollyish in my poor photo, and yes that side is West as the camera was pointing North. Just thought of another question. Some websites sell a non-waterproof liner that you put under your main liner like a carpet underlay. Any thoughts on that? Some sellers even recommend a three ply arrangement with another layer of the underliner on top, making a sandwich ...but I'd imagine this would make it near impossible to find leaks.