Grow a Crystal Garden

We had a slow weekend at home last month (sooo nice!), and decided to spend our Saturday afternoon doing science experiments. This crystal garden was so fun!

This experiment will produce very nice, broccoli-like salt crystals from readily available ingredients. They tend to be fragile… but quite beautiful. (Please supervise your children while doing this experiment.)

Supplies:

1 clear container per child (plastic-to-go dishes work well)

several small pieces of porous material to grow on per container (sponges, clay pot pieces, BBQ briquettes, etc.)

water

ammonia

laundry bluing (such as Mrs. Stewart’s Liquid Bluing (you can find it at Albertson’s/Macey’s); be careful, it stains)

salt

1 small paper cup to mix ingredients

1 plastic spoon

food coloring (optional, but highly recommended)

Procedure:

1. Put your porous material on the bottom of your dish.

2.  Mix 2 Tablespoons of salt with 4 Tablespoons of water in your cup, stirring to dissolve as much salt as possible.

3.  Add 2 Tablespoons each of ammonia and laundry bluing, again mixing as you go. The mixture will be a blue, watery sludge.

4.  Pour the sludge, liquid and extra salt, on top of the porous substrate in the plastic dish. Make sure to get all the salt out of the mixing cup and onto the porous items in the plastic dish. All the salt may not go into the solution; that’s okay as long as you pour the extra salt on top of the items in the dish. The porous materials in the dish will not immediately soak up all the liquid; this is okay.

5.  The crystals will naturally grow white, like the salt. If you want colored crystals, add a drop or two of food coloring on each item in the dish. The crystals will grow that color.

6. Allow the container to sit open to the atmosphere overnight. By the next day, crystals should have formed on the items in the dish and your crystal garden should be starting to bloom. Here’s a close-up of ours after 24 hours:

7. You can keep the garden “in bloom” by adding 2 more Tablespoons of salt on the second day, then half batches of the whole mixture from time to time. Make sure to pour the liquid into the base of the container and not on top of the already formed crystal blooms, as it will dissolve them and you will have to start over (which is also a lot of fun!).

**We discovered that the red and yellow food coloring didn’t “grow” as much. As you can see from our pictures, the blue and greeen were amazing! I’d like to do an experiment where we only use yellow and red to see what happens. (Maybe my kids put a lot more blue and green in their gardens?)