Grow Your Own Blob!

Grow Your Own Blob!

Grow Your Own Blob – Slime Mould Kit Guide

Slime moulds are one of those “what even are you?” creatures. They’re not plants, not animals, not fungi – just one big, living cell that can crawl, eat, and solve little puzzles.

Our Grow Your Own Blob kit lets you keep a tiny slime mould at home, watch it wake up, and see how it hunts for food. This guide walks you through:

  • What’s in the kit
  • How to wake up your blob
  • Day-to-day care
  • Common problems and fixes
  • Easy blob experiments
  • Safety notes for kids and grown-ups

Perfect for: curious kids, classrooms, and any bug nerd who wants a low-maintenance science pet.

What’s in the Grow Your Own Blob Kit

Inside each kit you’ll find:

  • Clear dish with lid
  • Round pads (the “bed” for your blob)
  • Tiny dried blob starter (slime mould)
  • Oat “blob food”
  • Water dropper
  • Tweezers

You’ll also need from home:

  • Distilled water (this keeps things cleaner and less mouldy than tap water)
  • A dark, room-temperature spot (cupboard, drawer, or inside the kit box)

Grown-up tip: young kids will need help with the water and tweezers.

What Is the Blob, Exactly?

The “blob” in this kit is a slime mould in a sleepy, dried state.

When you give it:

  • moisture
  • darkness
  • a little food

...it wakes up, spreads across the pad, and starts looking for snacks. You’ll see it as yellow or white branching veins reaching toward the oats.

It’s safe to observe and handle with normal common sense, but it is not food, not a toy, and not a pet to cuddle.

How to Wake Up Your Blob (Step-by-Step)

This is the basic setup we use in the kits. It’s simple and repeatable.

1. Make the blob’s bed

  1. Put one pad flat in the bottom of the clear dish.
  2. Use the dropper to add small drops of distilled water.
  3. Stop when the pad is evenly damp but not puddled. If you see standing water, gently tilt the dish and let the extra run off onto a paper towel.

2. Add the blob

  1. Place the dried blob starter on top of the damp pad.
  2. Put 1–2 oat flakes next to the blob (not directly on top).
  3. Put the lid on the dish.

3. Give it a cosy home

  1. Place the dish in a dark, room-temperature spot – a cupboard, drawer, or inside the shipping box all work well.
  2. Leave it alone for about 24 hours.

When you check it the next day, you should see thin yellow or white “veins” crawling across the pad toward the oats. That’s your blob, awake and exploring.

Day-to-Day Blob Care

Slime moulds are low effort, but not zero effort. Think “houseplant level”, not “rock.”

Daily checks

  • Look at your blob once or twice a day.
  • If the pad looks dry or the blob looks shrivelled, add a few drops of distilled water.
  • When the oats are eaten or completely covered, place fresh oats a little distance away so the blob has somewhere new to go.

Light and temperature

  • Slime moulds do not like bright light – keep the dish in the dark most of the time.
  • Normal room temperature is ideal. Avoid radiators, sunny windowsills, or cold basements.

When to change the “bed”

Every 5–7 days, or if you notice a sour/yeasty smell, it’s time to move your blob:

  1. Put a fresh pad in a clean dish and dampen it with distilled water.
  2. Use the tweezers to move a clean piece of blob onto the new pad.
  3. Add 1–2 oats beside it and put the lid on.
  4. Throw the old pad in the trash.

Troubleshooting: When Your Blob Misbehaves

1. “Nothing is happening”

If you see no growth after 24–48 hours:

  • Check that the pad is damp, not dry. Add a few drops of distilled water if needed.
  • Make sure the blob is somewhere dark and reasonably warm.
  • Some blobs are slow starters. Give it up to two days.
  • If still nothing, try a fresh pad and a different piece of the starter.

2. Fuzzy mould shows up

Fuzzy, fluffy growth = mould, not slime mould.

What to do:

  • Move a clean, non-fuzzy piece of blob to a fresh damp pad with new oats.
  • Throw the old pad in the garbage.
  • Use small food portions so oats don’t sit and rot.

3. It smells bad

A strong sour or yeasty smell means:

  • The pad is dirty and full of waste.
  • Move the blob to a fresh pad with new oats and fresh distilled water.
  • Toss the old pad.

4. Blob shrivels up

Likely causes:

  • Too dry
  • Too hot

Fix:

  • Add a few drops of distilled water.
  • Move the dish to a cooler, darker spot.
  • If it doesn’t recover, start again with a new starter piece.

5. Blob “escapes” the dish

Yes, it can climb if it’s hungry or overcrowded.

  • Make sure it has enough food and a fresh pad.
  • Keep the lid on.
  • If it creeps out, you can gently scoop it back in with a bit of card/paper, or wipe it up with cleaner and continue with the culture inside the dish.

Putting Your Blob to Sleep (Storage or End of Project)

When you’re done with the project or want a break, you have two options:

1. Let it dry for storage

  • Leave the blob on its pad in the dish and let it dry out completely in the dark.
  • Once dry, a grown-up can fold or cut the pad and store it in a dry paper envelope, or keep the whole dish dry and closed.

Later on, you can wake a piece of it up again using the same “wake up your blob” steps.

2. Dispose of it

  • Let the pad dry out.
  • Put the pad and any visible blob into a bag, tie it closed, and put it in the household trash.

Easy Blob Experiments (Kid-Friendly)

These are simple add-on activities you (or a teacher) can run once the slime mould is growing well.

Light vs dark test

  • Cover half the dish with cardboard or foil; leave the other half uncovered.
  • Check back over a couple of days.
  • Does the blob prefer the darker side? (It usually does.)

Snack maze

  • Place little oat piles at different spots on the pad.
  • Watch which path the blob makes between food sources.
  • Try changing the positions and see if it takes a different route.

Colour snack

  • Put a tiny drop of food colouring on one oat flake.
  • Offer that coloured oat along with plain oats.
  • Watch how the blob absorbs the colour through its network.

This is a fun one to time-lapse with a phone if you want extra science points.

Safety Notes

This kit is designed to be family- and classroom-friendly, but a few rules keep everyone safe:

  • Best used with adult supervision, especially for younger kids.
  • Do not eat any part of the kit or the slime mould.
  • Keep fingers away from eyes, nose and mouth while handling the dish.
  • Wash hands with soap after touching the blob, pad or dish.
  • People with asthma or strong allergies should avoid handling the culture directly.
  • Used pads and blobs should go in the household trash, preferably sealed in a bag if still moist.
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