How To - Make a floating casket spray

I received a call the other day asking if I could design a Casket Spray that would float.  Im pretty pleased with the final result, and photographed the process I used.  The challenge for the Spray was to provide a water source for the flowers - the funeral was taking place early in the day, to be followed by a dusk ceremony where the family would float the Casket Spray, with a lit candle in the river.  I decided to use Oasis floral foam, but then had the worry that with its weight when saturated it could possibly cause the whole design to tip.

My next challenge will be to design this in a more environmentally sound way.  If anyone has suggestions I hope that you will post.

I made the basic construction from styrofoam sheets 2cm thick.  I cut two oval shapes exact match. Into one I  cut a space to fit the oasis foam block I would use for the flowers. This cut sheet then became the top of the float.

I used Weldbond glue to adhere the styrofoam together.  I gave the styrofoam 24hours to adhere.

To neaten the look of the styrofoam, I painted it to blend with the oasis.

In attaching the oasis to the styrofoam base, I wired through the styrofoam up into the oasis tying off at the top, for added security I then taped it onto the styrofoam.  After making a hole for the candle, I used normal craft glue to glue it into the wet oasis.

I then greened up the oasis taking care to be sure to cover the stryofoam base.

The finished Casket Spray, ready to check that it will float evenly.

Floating in pool.

So now my question is how to do this again, but be environmentally friendly... ??

Michelle