Michael Bernstein found old versions of the seedballs.com domain (now apparently defunct) in the Internet Archive's Wayback Machine: Seedballs.Com Wayback Archive
Thanks to Al Pasternak of the Vancouver, BC Guerrilla Gardening Group,
for the seedball "recipe" and links to different sources:
http://commgardens.meetup.com/56/messages/boards/thread/2835980
5 parts clay, 3 parts soil, 1 part seed, 1 - 2 parts water
http://www.pathtofreedom.com/pathproject/gardening/seedballs.shtml
A. Dry terracotta clay, finely ground and sifted through a strainer to
remove large chunks of clay. Amount: 1 1/4 cup
B. Dry organic compost. Amount: 3/4 cup
C. 1/4 cup assorted seeds*. Various wildflower & vegetable seeds can be used.
STEP TWO: Mix B & C together. (Seed mixed with dry compost.)
STEP THREE: Add A to B & C mix. Blend everything together well.
Next, mist water onto the mixture while stirring. Spray just enough
water to allow the mixture to stick/bind together.
STEP FOUR: Take a pinch of the finished mixture and roll (in the palm
of your hand) into penny-sized round balls.
STEP FIVE: Put seed balls in the sun to dry completely for a day or two.
STEP SIX: Broadcast seed balls onto dirt area. Water or wait for
rain to allow seeds to germinate.
Makes approximately 30-40 balls
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