Ambitious Newbie considering a hugelkultur island

I can't tell if this idea is overly ambitious and impossible, or just pure genius, so I figured I'd turn to you all and open the floor for comments-

I'm constructing a pond, which I would like to be a good size, and I'd like to put an island in. Obviously I'm skeptical of the viability of a small island in terms of stability, and so I thought hugelkultur could help. The pond will be more of a still, circular stream because of the island, with a lobe or so (of pond) added in to increase size and provide an organic look. As I have not yet measured it out fully (im in the earliest stages of planning it) I can only provide a rough image: water width would be a minimum of 2-3 feet where the bridge is, to a maximum of somewhere around 6-8 ft at adjacent sections. Having never built a pond before, Im not sure how deep to make it but I imagine 3 or 4 feet would be a good compromise so as not to make the island a pedestal and to avoid algae.

ANYWHO, as you figured I thought hugelkultur would be a good foundation for such a feature, but would it be enough? And what could I be sure to do to ensure that it stays put? Currently planning on using Sunshine Mimosa as a ground cover for the island, as it is supposed to provide erosion control.

no harm in asking right?

So far the only strategy I've developed is to criss cross the logs so that they aren't as likely to roll out to the sides and flatten into a layer.

William Donald wrote:I can't tell if this idea is overly ambitious and impossible, or just pure genius, so I figured I'd turn to you all and open the floor for comments-

I'm constructing a pond, which I would like to be a good size, and I'd like to put an island in. Obviously I'm skeptical of the viability of a small island in terms of stability, and so I thought hugelkultur could help. The pond will be more of a still, circular stream because of the island, with a lobe or so (of pond) added in to increase size and provide an organic look. As I have not yet measured it out fully (im in the earliest stages of planning it) I can only provide a rough image: water width would be a minimum of 2-3 feet where the bridge is, to a maximum of somewhere around 6-8 ft at adjacent sections. Having never built a pond before, Im not sure how deep to make it but I imagine 3 or 4 feet would be a good compromise so as not to make the island a pedestal and to avoid algae.

ANYWHO, as you figured I thought hugelkultur would be a good foundation for such a feature, but would it be enough? And what could I be sure to do to ensure that it stays put? Currently planning on using Sunshine Mimosa as a ground cover for the island, as it is supposed to provide erosion control.

no harm in asking right?

Wow can't wait to see how this comes out. I've seen a video or show about floating beds in a pond and have always liked the idea. Can't wait to see how it turns out.

I think what you are describing would better be called a chinampa. I don't have any personal experience with them, but I understand they can be among the most productive growing methods known to man.

I looked up chinampas, but they are a lot bigger, and the 'island' structure is only made by putting in an underwater fence and filling it with shtuff. I assume the pond lining will essentially do that, although I'll probably reinforce it with the addition of stakes -it couldn't hurt.

stakes thru a pond liner ?

rethink required.

You want to create "edges" in a pond, just like in a forest garden.

consider an iron cross design to keep the heat down, and edge surface area up. oxygenation is key, and you need habitat for salamanders or frogs. They will help with stuff larger than mosquitos.

Criss cross all the way across, and use the bridges to allow circulation ?

no not through the liner, at the edges of the island, which the liner surrounds. Could you elaborate on the iron cross design?

i have a small island in my pond, you can view it in the blog in my address section..look up the pond threads.

Mine however is not hugelkulture..but there was cattail roots and tree roots that got buried under the clay of the island..which made it fairly fertile. I have planted some perennials and a medlar tree and some bushes on it..along with a waterfall with rocks and a bench from a section of telephone pole

not only is that the coolest pond i've ever seen, but the most beautiful property I have ever laid eyes on!
Go you!

I dont have enough clay for a natural seal, so Im going to attempt to find enough liner to cover the space needed, although I havent found out exactly that will go.

either way thanks so much for the glance at your pond!! Can you tell me what kind of grade the slope coming from the island is?

as a sidebar to this topic, thought you all would be interested in this video, an episode of Around the World in 80 Gardens:

https://www.youtube.com/watch?v=b6K03Wn1b1w

there's a segment on the ancient chinampas outside Mexico City. also a segment at the end on the organiponicos in Cuba.
pretty fantastic viewing.

Well I'm not sure what you are asking about the island..but it varies around the island..where the bridge is ..at top water leve it is about 30 inches deep on the north side of the bridge and under..but to the south side of the bridge there is a HOLE that is about 10 ' deep more more when the pond is dry, so that plus the water level on top would be about 13' deep there, I have a bubbler in the hole for the winter right now. That hole is SOLID CLAY..Joel tried digging as far as he could with a small backhoe, and he dug till he couldn't get the backhoe in there any deeper..and the area where the backhoe was sitting was a bit deeper than the highest level..he never got a buketload out that wasn't solid clay digging that hole.

On the south side there is a bit more shallow slope away from the pond, the East side is a little deeper but not really any drop off there and the North East is quite shallow slope away from the island.

We do have a problem with cattails wherever there is shallow water..so the edges of the island have cattails on the borders where the water and soil meet. I have gobs of plants planted in the pond of all kinds ..water lilies and lotus, as well as other pond plants, but the wildlife tend to tear them up pretty badly in the summertime.

we did hit some white sand on the North end of the pond in a band on top of the clay, but otherwise there is just clay clay clay.

the slope TO the pond is fairly gentle..from our house and our son's house..but most of our food forest and gardens drain into the pond as well as the lawn ..there is a drain ditch to the east of the pond that carries off water from the neighboring properties back to a wetland North of the pond and behind the house, as there may be contaminates in that water from the roads, neighbors, etc...we don't let that water go into the pond.

we built a bank on the north side of the pond between the pond and the wetlands, and the pond overflow goes into the drain ditch as well. The property also has some french drains that drain into that ditch..but the pond gets plenty of water as our property has a very high water table.

thanks for the compliments on the property ..I totally love it here

i saw an article where people built raised beds out of the fabric that is used to prevent erosion ..i believe the article was on the backwoods home website.. you might be able to sew two ends together of the erosion fabric with something that wouldn't pierce your liner..and fill the sewn BAG with blunt ended log pieces and soil and compost..to make an island..you wouldn't want sharp sticks or roots that might possibly pierce your liner..and you will want your liner to go UNDER the island otherwise you will have leakage..where the liner doesn't go..

there are a lot of good articles and books available for building ponds with liners..i didn't need a liner so I don't have a lot of info for you on that though.

you can also create floating islands..by using something that will float to hold it above the water..the fish in the pond then can feed off of the roots that go down into the water..some hydroponic set ups have fish below their plants. styrofoam or air filled chambers will help things float..also if you live in a really cold area you can float a "greenhouse" of some sort to magnify the sun into the water to keep an area free of ice in the winter..i have been meaning to try some floating islands with plants and also the floating glass or plastic "greenhouse" type thing to help with winter weather keeping small areas open and warmed..

good luck

awesome, thanks for all the info!
I'll be planting a magnolia in the "island" (itll be more of a peninsula, a Florida with a swollen everglades, if you will) so Im gonna leave the hugel bed open and laid in the soil, with the pond liner wrapping around it almost completely.
So far I've got the design all planned out in my head and somewhat on paper, I just need to finalize my plans for the rest of the garden, get the budget approved and start digging! Ill post pictures when its done