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Grow Your Own Monster Salt Crystals

grow your own monster salt crystals

This year my 5 year has started studying Science as a subject at school. He’s been coming home full of stories so I thought we could try some simple science experiments at home. As it’s Halloween our first experiment has been to grow our own Monster salt crystals. It’s surprisingly easy so I thought I would show you how we did it.

You will need:
A saucepan
Epsom Salts
Food colouring
Empty glass jar with the label removed
Large metal washer
Wooden stirrer
Bakers twine

How to grow your own Monster salt crystals:

Tie a metal washer to a length of Bakers twine and attach the other end to a wooden stirrer. Make sure the washer hangs about 2 inches from the bottom of the jar.

grow your own Monster salt crystals

Roughly measure the capacity of your jar and pour this amount of water into a saucepan. Boil the water then add about 100g of Epsom Salts (which I bought from my local independent pharmacy). Stir the mixture until the salt had dissolved, then add between 50-100g of the Epsom Salts, basically until the salt doesn’t dissolve any more. At this stage you can add a few drops of food colouring but don’t put add too many. Set aside the saucepan and leave to cool.

grow your own Monster salt crystals

When it has cooled down pour into your jar. Place the wooden stirrer and washer into the mixture.

grow your own Monster salt crystals

Then you can watch the crystals form as the water evaporates. We left ours on a windowsill so it was easy to see the crystals grow.

grow your own Monster salt crystals

The children were pretty impressed that we grew the crystals ourselves.

grow your own crystals


We thought this was a fun craft for this time of year. Let me know if you’ve ever tried this fun experiment.


  • Reply
    October 29, 2015 at 11:00 am

    This looks like a great fun activity for parents and children to do together 🙂 It looks fab!

    • Reply
      Tori Gabriel
      October 29, 2015 at 1:30 pm

      I love doing science experiments with the kids. I saw an awesome one on FB the other day using milk, washing up liquid and food colouring but it didn’t work for me! No idea why!

  • Reply
    Laura Hartley
    October 29, 2015 at 2:50 pm

    I’m very impressed with these!!! If you used green colouring instead this could look like a Christmas tree 🙂

  • Reply
    Sarah Bailey
    October 29, 2015 at 9:52 pm

    This looks such fun – I remember growing salt crystals when I was younger nothing this size though! x

  • Reply
    Helen Dickinson
    October 29, 2015 at 10:03 pm

    I love this post. It is a fantastic activity for the children to do ahead of Halloween. Max would love to make these salt crystals.

  • Reply
    Aimee Foster
    October 30, 2015 at 8:49 pm

    Am going to try this with my 6 year old who is very interested in science. She will love this – thanks for sharing!

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