How To Make A Floating Island
Step-by-step instructions for building a floating plant island for ponds (or you can buy one)
Step 1
Draw the shape of your island on a piece of cardboard, we used a green file folder because we had one handy. We drew our island shape that looked a bit like a bif footprint. You could make any shape island you want. We're going to try different shapes but this was our first attempt at building a pond island so we'll use it.

Use a big black marker to trace the shape of your template onto the coarse filter material. We used a 2" thick piece.
Step 2
Use the carpet-knife or box cutter or sharp blade to carefully cut the shape of your island out of your piece of filter material.

We then traced and cut another island shape the same as the first so we could put one on top of the other to make the island thick enough.

We tried to put our template for tracing as close to the corner adge as possible so we could make many islands out of the large 5' x 5' piece of filter material we had.
Step 3
Once we had our two identical shapes cut out of our 2" filter material we chose one as the top section and carefully carved out a "bowl" in one of the sections. We wanted a bowl to hold the soil for our plants so with our 2" thickness we carved out about 1.5" so we had about half an inch at the bottom of our top island section.

We left about 1 or 2 inches of an edge around the section.
Step 4
In this first attempt at building our diy floating pond island we wondered how to make sure the top and bottom sections stayed bonded togeher.

Our first idea was to sew the section together using fishing line. We used a sewing needle and some clear fishing line to sew the top and bottom section together. It worked well!

We didn't try and do really close stitches, just enough to hold the island together while we did the final shaping.

The foam that you will inject to provide the boyancy will also help hold the two sections together as it will expand between the fibres and lock together.
Step 5
Carefully shape the island. We used scissors to just slope the edge of the island so it was smooth and even. Be careful l not to cut the fishing line that holds the two sections together.

This final sculpting really made the island look nice!

We were starting to get excited about the progress!
Step 6
To be able to inject the foam into the filter material you need to poke some holes into the island. We used a screwdriver to poke holes through the island. We basically made the hole go all the way through the island.

Poking a hole with a screwdriver was the only think we found that worked...we tried a drill but it just wound up around the filter materials so poking holes seemed like the good old fashioned way that worked best!
Step 7
Slowly inject the waterfall foam or expandable foam into the holes you poked with the screwdriver. The foam expands to many times the original spray size so go slow. The cans of foam come with strawlike injectors so you can just push the injector into the hole you make in the island and slowly...slowly release the foam.

For this small island I used about 2 or 3 ounces of a 12 ounce can of foam.

I had poked about 10 holes in the island. I will try different amounts in new floating island projects once I see how this one floats.
Step 8
Let it dry.
After we injected the foam into the holes we added a few squirts between the two layers on the edge...for this first proto-type we just eyeballed it...the foam expands so much that after you do a small squeeze you can see it expanding into the fibers of the matrix.

We let it sit on a piece of cardboard so none of the foam would drip onto the grass. It only took a couple of hours to dry and then we trimmed off any bulbs of foam that had formed in on the island.

Step 9
After our island dried we took it to the pond to test it out. It floated! We were so happy and the fish were very curious about it and right away were swimming underneath it!

So it passed the float test and now we just needed to go and plant some plants into our floating island.

Step 10

In this picture we placed our homemade floating pond island next to one of the commercial ones we have had in our pond for the last 5 years.

Here is a picture of the island we made beside our commercial island we were going to borrow plants from.

Our little white island looks pretty sad next to the fully bloomed island but when the commercial island was planted years ago it didn't look much better so we decided not to let appearances bother us!
Step 11
We start by using an aqutic planting soil and some peat-moss and rubbing it into the island. We soaked it with a hose and rubbed the soil mix with a bit of peat into the island. We could see that the soil mixture started filling the spaces between the white fibres of the island.

As we rubbed the island started to become brown...we were getting happier with our project!

We borrowed some of the plants off our existing island to start our new pond island.

Some of the root sections we wanted to transpalnt were pretty big and so we used a knife to slice deeper holes into our new floating island. We were cutting into the foam as well, basically digging a hole to fit the root ball into the hole.

Step 12
Here is the finished product fresh off the assembly line!

Not too shabby!

So now we need to put this island somewhere to test.


Our backyard pond is a bit too small for another island sincwe we have two already so we ent out and bought one of those half barrels to use as a mini water garden on our back deck.

Step 13
Here is our floating island in the "test pond"! We added some of the water hyacinths that were growing like crazy in our pond to the barrel to create a nice ring around our freshly planted floating island which sits in the middle.

We actually had to add a few rocks onto the island as it was sitting high in the water the first two days but then it seemed to lower in the water and we removed some ballast.

What a fun project! We already want to do it again! We are already planning our next project to build a do-it-yourself floating pond island!

We will upload photos of the island as it progresses...we could already see that the plants we moved from the other island weren't too happy about being transplanted in August but we had no choice...the other islands were tipping over from too many plants that were too tall!

Building A Floating Island
Instructions for a small homemade floating island
Version One - Our First Island : This is for an 18" x 10" floating island

Required Materials We Used

Coarse Filter Material
1.5" to 2" thick filter medium available at any pond store or aquarium store. It's the same filter material that is in pond filter falls or in biological filters. Usually comes in white, blue or black with different densities. Any fish safe pond filter material will work. There are some cheap filters for furnaces and dust collection systems but you should use a proper filter material used in pond skimmer or filters so you know it will last and won't hurt your fishies.

Waterfall Foam
The same expanding foam that is used in building a pond waterfall can be used to provide bouyancy for your homemade floating island. You will need less than a can for the small island. We wanted to use the Rockin'Foam™ waterfall foam but didn't have any so we bought Great Stuff™ insulating foam sealant. Because the filter material is white the yellowish color of the Great Stuff foam was a little less obvious. We are going to try a black coarse filter material next time and will use the black pond waterfall foam so it hides better.

Carpet Knife/Box Cutter or Heavy-Duty Knife
You will need to cut the filter material into the shape you want. A long blade can make the job easier. A box cutter type of blade with a secure handle and adjustable steel blade can do the job.

Screwdriver & Scissors
Something to poke holes in the filter medium so you can inject the foam into the holes. Scissors can be good to do the finishing to sculpt the island smooth and make nice conoured edges.

Fishing Line and Heavy Duty Sewing Needles
We sewed two layers of the cut and shaped filter material together to create a thicker floating island. It was a nice experiment! Using a large 2" straight needle and a 3" curved needle we were able to sew the layers together and then sew the edges together almost like a hem.

Commercially Available Floating Islands and Floating Planters

Islandscapes, Floating Island Ecosystems for ponds and water gardens. Islandscapes provide many advantages to the pond owner: beauty, fish and wildlife benefits, and natural filtration. Islandscapes are made of recycled plastic biomesh bonded by buoyant foam. They are pesticide and herbicide free, and durable enough to withstand hard winter freezing.

Each island contains: Tether ring for anchor, Islandscapes growing media, Instructions for use, 5 year warranty Plants not included Islandscapes can grow almost anything - herb gardens, terrestrial flowers & shrubs. You can even grow vegetables and fruit on your islands as well as bog plants. Islandscapes provide shade and safety from predetors. Roots and concentrated nutrients have a tasty "floating supermarket" effect that is beneficial to fish growth. They also provide habitat for frogs and turtles.

Islandscapes attract and bond suspended solids. The open matrix and the plant roots provides floating phytofilter, a true four-stage biological system that removes phosphates, ammonia, nitrates and nitrites. The effect on water quality is dramatic and completely chemical free. Plants growing on islands are 2-5 times more efficient in removing pollutants from pond water than plants in pots.

Floating Planting Basket

The Laguna Floating Plant Basket is ideal for ponds that don't have adequate plant shelves. The Laguna Plant baskets make planting and maintenance easy. Made of finely-woven fabric, the plant basket provides excellent soil containment and protects plants from fish. The baskets are made with buoyant Styrofoam that ensures the basket says at the surface and the plants are easily anchored to ensure they stay securely in place.

20" Floating Island Planter

20" foam collar with a 16" x 7" plastic liner. Protects plants from grazing koi fish and goldfish. Self watering design. Constructed of heavy duty foam for long life. These floating islands can be used in an existing watergarden or you can use the island in a water filled container or half barrel as a self-watering system. Soil not included.

Pond Kits & Water Gardens

Just Add Fish and Plants and You're Ready to Enjoy the Wonders of a Natural Ecosystem. This is an introductory pond kit and can be used by a novice or first time ponder to build a simple pond. It comes complete with liner, pump and tubing. Everything you need to start your pond. Kit contains the following items:. 10ft. x 12ft. nontoxic, polyethylene liner for a 6ft. x 8ft. x 18in.D pond. 3 planting baskets. Fish-safe, energy-efficient pump and tubing to aerate water and keep fish and plants healthy. Clog-resistant, adjustable fountainheads that spray two patterns: fleur de lis and dome. Starter water treatment and conditioner for proper water balance. Natural pad of barley straw for clear water. Complete instructions for assembly and maintenance. Rocks not included. U.S.A.
Pond Kits & Water Gardens
Leave A Comments!
We'd love to hear from you about your island building project or any comments or advice you may have forother do it yourselfers!

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What is a floating island?

A floating pond island is like a floating pond planter only better. It is a floating island that can drift arounbd your pond that is full of plants. Anything from grasses to irises will grow. You can plant almost anything into a homemade floating island.

There are commercially available versions of floating islands and floating planters but they are costly.

With a few simple tools and some readily available products you can build your own floating island and have it planted and floating in your pond in only a few hours and much cheaper.

It is also a great project!

If you want, there are floating islands available online for a few hundred dollars up to many thousands of dollars but if you want to build a cheap floating island for your pond then you can follow our step by step instructions to see how to build a floating island.

Fish love floating islands and can hide under them and shade themselves from the sun. Floating Islands become a habitat for frogs and birds and larger islands can become a haven for larger creatures.

The plant roots grow into the pond and provide filtration and reduce nutrients. Apparantly the material used to build the islands acts like a biological filter. There are commercially available versions of floating islands and floating planters but our instructions show how to build your own exactly the size and shape you want for way less money..

For DIY people like us we wanted to share some easy ways to build your own floating island..

We already had two floating islands in our small backyard pond and they were fantastic. They have been with us for 5 years now and we have kept them in our 500 gallon pond over each winter and they came back and grew like crazy every season. When we decided to build our own floating island it was more about trying recreate the obvious simplicity of the system...they were bought for $150 each and they are worth every penny but we wanted to try and do it ourselves.

Now that we have we want to share the diy step by step instructions for building your own floating island. It might be easier to buy a commercial island but we wanted to prove we could build the same thing or better for much cheaper!

You can too!

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