The seed grenade in this instructable is inspired by the Flower Grenade available from SUCK UK (http://www.suck.uk.com
). It doesn't look quite as polished but it does the job and costs much, much less.
The basic idea of the seed grenade is a clay container which contains seeds and a growing medium, that breaks on impact with the ground, allowing the seeds to grow. It's a fun project to do and the results can look pretty good after the plants or flowers have grown.