Growing Seeds in Sponges – Our Fun Home Ed Experiment

Ever heard of growing seeds in sponges? We gave it a try as part of our home education science lessons — and it turned out to be such a fun, hands-on project for all ages. It’s clean, easy, and fascinating to watch!

We used a big basin and some old bath sponges that I washed in the washing machine first to make sure they were nice and clean. Then the kids chose mung beans and lentils to experiment with because they sprout quickly (perfect for impatient scientists).

🌱 What You’ll Need

• Clean bath sponges (natural or cellulose ones work best)
• A shallow tray or basin
• Water
• Quick-sprouting seeds such as mung beans or lentils

🔬 How to Do It

1. Dampen the sponges – Squeeze them until they’re moist but not dripping.
2. Add the seeds – Gently tuck the seeds into the sponge’s holes so they’re snug against the damp surface.
3. Find a bright, warm spot – A sunny windowsill or somewhere with indirect light is perfect.
4. Keep them moist – Check daily and top up the water if needed.
5. Watch them grow! – Within a few days, tiny roots and shoots appear.

We kept ours in a basin so that any extra water could drain, and the kids loved checking each morning to see how much the little sprouts had changed overnight.

🧒 What Kids Learn

• What seeds need to grow (warmth, water, and air)
• How roots and shoots form
• The difference between sprouting and planting in soil
• How to record growth and make simple observations

It’s also a brilliant way to reuse old materials and show how learning can happen anywhere — even in a sponge!

🥦 Can You Eat Them?

That’s the big question, isn’t it? While mung beans and lentils can be eaten as sprouts when grown cleanly for food, these ones aren’t for eating. Bath sponges, even when washed, can still hold traces of soap or detergent, and they’re not food-safe.

For curious little ones who want to taste their sprouts, it’s better to start a fresh batch in a clean jar or sprouting tray designed for food use. You can read how we do that in our post: 👉 How to Sprout Seeds to Eat.

🌿 What Happened Next

Once our sponge sprouts had grown tall and sturdy, we decided to plant them outside. We put the whole sponge straight into the ground — and it actually worked! The sponge held moisture around the roots at first, and as the plants established, they grew just like any other seedling.

It’s a fun way to extend the experiment and connect it to real gardening — showing the kids that learning can move from the kitchen windowsill right into the garden.

🌞 In a Nutshell

This simple project is fun, mess-free, and full of science learning. The kids get to reuse materials, make daily discoveries, and see real growth happen before their eyes — all from a few seeds and an old sponge.

Enjoy and let us know how your sprouting goes…