Growing Grass: A Sunlight Experiment

I’m talking about another experiment you can do with your littlest learners today! The kids and I are discovering all the treasures a garden holds with our Garden Treasures box from Experience Early Learning. Our first week was dedicated to learning all the things that go into planting a garden including Sunlight and Water. What better way to bring this concept home than with an experiment!?

As an Experience Early Learning (EEL) Blogger, I receive the EEL Preschool Curriculum in exchange for my honest opinions and authentic stories about our experiences using the curriculum. All opinions and thoughts are completely my own.


Can grass grow without sunlight?


My daughter knew that seeds need soil, light, oxygen, and water in order to grow. I asked her, “So if I hid a cup of planted seeds in a cabinet would it grow?” I don’t think so she replied.


  • Plastic Cups
  • Permanent Marker
  • Soil
  • Water
  • Measuring Cup- we used a medicine cup to measure 10 mL of water)
  • Rye Grass seed (grows quickly)
  • A safe spot to place a cup where it can receive sunlight and one where it can not receive sunlight

One of the absolute best things about Experience Early Learning is that they send me items in our discovery bags that I normally do not have on hand at home. They sent the plastic cups, rye grass seed, and even the soil (even though we used our own). When you have all the supplies at your fingertips, there’s no excuse to not get your hands dirty- literally and figuratively.


I know it is pretty self explanitory, but the thing you have to remember with experiments is to only change 1 variable. This makes measurement very important.

Since we are changing the amount of light the planted seeds will receive, the amount of soil, seeds, and water should all be the same.

With that in mind, the kids filled their cups up to the line on their plastic cup. Then they used their finger to make a little hole and placed about 1/4 tsp of rye grass seeds into their hole. They covered the hole a little with their finger, then placed 10 mL of water over their sown seeds.

I marked each cup with their initial and the date, so we could see whose grew and how long it took. We were going to leave our cups outside; however, the rain has been terrible here lately, so the kids placed their seeds on the window sill in the house where they could easily observe their growing grass. My cup of planted seeds were placed in the bathroom cabinet that hardly gets opened.

Now the hard part… waiting.


I’m so glad we kept our cups in a place we look at everyday so we wouldn’t forget our experiment! After 3 days we had tiny little grass sprouts, but in 6 days we had this! (see below)

The kids rye grass has taken off! We went to the bathroom cabinet to see if the one without sunlight grew. It had not grown at all, but there was something living in the cup- a SLUG! (We did some fun slug learning awhile back, which you can read about here) I could not believe it. I guess it was in the soil bag we had that had been stored outside. I should have used the soil Experience Early Learning sent us, lol! The kids were tickled to death to see a slug, but we sent it on its way outside in our front yard.

Experience Early Learning sent us this perfect Observation Record with 4 spots to encourage us to keep observing our growing grass. We are going to observe it again in a few days and record our measurements for day 9. However in 6 days it has grown over 7 centimeters!

My 6 year old’s observation sheet. My 3 year old just scribbled all over his.


I asked my kiddos our question again:

Can grass seeds grow without sunlight?

They both gave me a resounding “No.” Then they asked if we could place my cup on the window sill and see if it will grow, which is where my cup is now as I type this. I has little tiny sprouts after 1 day of sunlight!

If I did this experiment again, my question to the children would be:

What do you think we need to grow grass? (soil, water, sunlight)

I then would have a cup with all 3 needs present, a cup only with seeds, sunlight and soil (no water), a cup in a cabinet with only seeds, water and soil (no sunlight), and a cup with seeds, water, and sunlight (no soil) and see if any of them grew. Obviously the one with all the needs would grow, but that way the children would see that seeds need ALL 3 and not just 1 or 2 needs met.

Hmmm…. I still have some rye grass seed left over… we might go ahead and set this experiment up today….

More Garden Treasure Fun

Be sure to check out these blog posts about more garden themed fun!

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