Seed balls are a method of plant propagation widely promoted by Japanese natural farming innovator Masanobu Fukuoka.
There are plenty of variations on how to make them, and this video gives you some great general pointers.
Seed balls are simply seeds mixed with equal proportions of dried compost and clay, formed into balls, and dried for later sowing. They are compact, easy to handle when dry and range in size from a gumball to a baseball.
The genius of this idea is that they only separate and fall into the ground when there is enough rain to dissolve the clay, which will of course will also provide ample water for germination.
Certain seeds work better than others for seed balls. Skip the thick-skinned seeds, and some seeds need heat or cold to bring them out of dormancy.
Seed balls-- or bombs, are perfect for guerilla gardeners everywhere! What a great way to bring plant life to an unused space.
Get everyone together and start bombing those vacant lots in your neighborhood with seed balls!