Grow a Sponge Garden

seeds with roots

See how a seed starts to grow roots by make a simple sponge garden.

What You Need

  • Cup
  • Dark cupboard
  • Seeds – bird seed works
  • Sponge (optional)
  • Spray bottle (optional)
  • Towel, paper or fabric (optional)
  • Water

What You Do

  1. Soak seeds in water.
    We recommend you soak the seeds overnight, especially if they are older seeds.
    We found large seeds like sunflower seeds worked the best for this project.seeds in glass
  2. Dampen the sponge or towel.
    We tested the sponge garden activity with a variety of sponge types – natural, artificial, paper and fabric towels. We found any type worked.
    Put your sponge or towel on a plate before getting it damp because you will need to move it, and you want to protect the surface underneath it.
    We tried the garden where we pushed the seeds into the holes of the sponge, but we found it didn’t make a difference whether the seeds were just on the sponge surface or in a hole.sponge garden start
  3. Place the sponge or towel in a dark cupboard for a day or two.
    Depending on how dry it is in your home, you might need to spray the sponge or towel once or twice during this time. But typically, the initial spritz is enough.sponge in cabinet
  4. Check for roots.
    Once the seeds start growing roots, you can move them to soil and grow them in sunlight.
    Check out the terrarium activity.
    Ask Your Child:

    • What do seeds need to begin to sprout? (Water and warmth)
    • What do you think the sprouts need to grow into healthy plants? (Water, sun, and soil)
    • Why do you think seeds grow well in spring?

    seeds with roots