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.
Step 1: What You'll Need
You're going to need the following items in order to create your own seed grenade.
1) Clay working tools
2) A spoon
3) Gloves (optional but nice)
1) A ball of air hardening clay
2) A selection of seeds
4) Paint (optional)
Step 2: Making a Hollow Ball
First off, rip off a section of your clay and start working it in to a ball. A ball will be the base shape for many of the things that you will make, as they're the easiest to hollow out for the compost and seed mixture.
When your ball is nice and round, start to work your thumbs into it from the top, hollowing it out as you push your fingers and thumbs in further. Squeeze the sides as you're doing this to make the walls thinner so it is easier to break after it dries.
If you find that it's too big after you've worked the clay for a while, just rip a bit off and work it again until you're satisfied.
Step 3: Filling Your Ball
At this point you should have a hollow ball or jug shape, so it's time to fill it up with your compost and seeds.
Start by taking your spoon and loading up some compost on to it, in the picture below I used a small trowel as the cutlery drawer was too far away, so yours should end up a little less messy than mine did.
You should be alternating between compost and seeds in order to get a good spread in your grenade, though once it's smashed up it won't really matter that much.
When it's full, pinch the top together into a neck for your grenade.
Step 4: Decorating the Grenade
Now is the harder part, decorating the blob of clay to make it look more like a grenade. We used some clay tools in order to make markings and rolled up a little pin out of some scrapped clay from earlier.
Start off with the pin, roll it up into a small sausage shape on a flat surface, then attach it to the main body of the grenade as shown in the second picture. Feel free to take some artistic license on the grenade pin.
After it's attached, start to score the grenade to give it a more recognised grenade look, keep decorating until you're happy with how it looks and then put it to one side to dry.
Step 5: Finishing Off
When your grenade has dried, it is time to add the finishing touches. We decided to leave the grenade plain rather than painting it, but as you can see we also made a green chilli and a strawberry (I got bored making the dimples after a while) with poster paints, which dry very quickly. All that's left to do now is use the grenades, either by giving them as gifts to green fingered friends or using them yourself to make flowers bloom almost anywhere.
Step 6: Final Product and Thoughts
After all the hard work involved in making your seed grenade, it almost seems a shame to use it for it's intended purpose, which is to be smashed and give the seeds inside a chance to grow.
Thoughts on this instructable are that we made the grenade too small, as when broken it was clear that there wasn't enough compost in relation to clay, and also that the clay was a bit too thick to be broken properly when thrown.
A further idea on the clay would be to substitute the air hardening clay with a salt dough recipe, as this would be more biodegradable than the clay itself. However, the recipe for the dough would not be able to contain salt, as this would stop the seeds from germinating properly.
Another thought would be to incorporate a water balloon into the finished, larger recepticle in order to water the plants when the grenade is smashed and the balloon is burst. However, this would have to be a biodegradable balloon in order to minimise litter.
Any thoughts or comments on this or any other matter are welcomed, as input from other people can only make a project better, and no project is perfect on the first try. Thank you.