4 tbsp. non-iodized salt
4 tbsp. liquid bluing
4 tbsp. water
1 tbsp. ammonia
Food coloring

Spoon over bits of porous material rock, board, sponge, charcoal, etc. Have solution cover the bottom of the container. Drip food coloring over garden. Use more than 1 color for a colorful effect. Now watch this garden grow.