"Grow " a Crystal Garden
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What you'll need:
a medium-sized glass or plastic bowl
some pieces of brick, cement coal or a sponge
"bluing" (you can get it in the laundry cleaners section in the grocery store)
6 tbsp salt
4 tbsp water
food coloring

 Put pieces of coal, brick, cement or sponge in the bowl.

Day 1:
On the base material, pour two tbsp water, two tbsp table salt (iodized or plain)
and two tbsp  bluing.
Day 2:
 Add two more tbsp salt.
Day 3:
 Pour into the bowl (not on the base material) two tbsp each of salt, water, and  bluing
 color each piece with a drop or two of food coloring

  If  a flower-shaped form hasn't happened by now, add two tbsp ammonia. Let the air get to it...don't cover it up. It also works better in dry air conditions.

If you want it to keep "growing", add more bluing, salt and water. It'll keep going until you want it to stop! Have FUN!

 Does It Grow?

No, crystals form, but, they sort of look like they're growing, because they get bigger.

The salt is dissolved in the water.
As the water evaporates, crystals of salt form on the base material.

 "Bluing is a colloidal suspension of extremely minute particles of blue powder (Ferric Hexacyanoferrate). This is not a solution in the true chemical meaning of that word.

As the water from the bluing and the clear water which is first added evaporate, two things happen. The blue particles can no longer be supported and the excess salt cannot stay in solution. The salt crystallization process will take place around the blue particles as nuclei, in much the same way as silver iodide cloud seeding accelerates the formation of rain drops.

Small amounts of ammonia are added chiefly to speed up the evaporation process.

The purpose of the porous material (sponge pieces) is to provide a means for capillary action to carry the liquid containing bluing and salt up from the main source of liquid. This further speeds up evaporation and causes the crystals to form over a larger area than just the rim of the bowl.

Additions of bluing and salt on later days should be made by slipping the new liquid in below the rest of the growth. Capillary action will bring this further material up where the evaporation can cause additional formations of crystals.

No chemical reaction takes place in this process, just dissolving and recrystallization aided by the bluing particles."