Your kids will love growing beans in a bag because they can watch the beans go through the different stages of the plant life cycle. It’s an easy and interactive way to teach your kids about plant biology!
Growing plants in soil is a wonderful way to introduce kids to botany and the life cycle of a plant. However, the kids don’t get to see what’s happening to the seed underneath the soil.
Growing beans in a bag is like creating your own little greenhouse at home and allows your kids to watch the seeds sprout. All you need is a Ziploc bag, paper towel, and some dry beans and you can germinate seeds in a bag.
Your kids will love watching their beans grow their first roots. If you have a magnifying glass, you can also look closely at the root and see that there are tiny hairs on the root that absorb water.
You can use dry beans sold in grocery stores for this experiment. However, do note that some beans may be too old to germinate well. I recommend getting quality bean seeds (we got lima beans) if you are doing this experiment for the first time so your kids don’t get disappointed if the beans don’t sprout.
Germinating Seeds in a Bag Experiment
- Bean seeds
- Paper towel
- Plastic bag
1. Fold the paper towel so that it fits nicely inside the plastic bag. Wet it with some water. You don’t want the paper towel to be dripping wet but it should be decently damp. Insert the wet paper towel into the plastic bag.
2. Place the seeds inside the plastic bag on top of the wet paper towel. I recommend placing the seeds at least 1 inch apart so that you can see the roots well when the seeds sprout. If you place too many seeds in the bag the roots will become entangled and more difficult to see the details.
3. Seal the Ziploc bag and place it in a warm, sunny spot. If you wish, you can even tape it to the window, but just make sure that the seeds are on the inside so you can keep track of it daily.
Depending on the seeds, you may see them sprouting after 24 hours. Ours took until the 3rd day to germinate. You can see the hard casing cracked open and the embryonic root (called radicle) developed. The root grew so fast overnight that before we went to sleep the seeds were intact, but by the time we woke up they looked like this:
The bean seed growth accelerated after this and root hairs began to grow. Here is what the beans looked like on the 4th day:
By the 5th day, all of the bean seeds had root hairs.
On the 8th day, you can see the first leaves started to poke out. The root system had also grown quite a bit. At this point, the beans were ready to move to soil. You can plant it in a planter or straight in the ground. Just make sure you plant the germinated seeds in a sunny spot where they could get plenty of light for photosynthesis.
We decided to keep the bean plants in the bag and continue to monitor their progress. How far in the plant life cycle could a seed go in a plastic bag?
Two days later, on the 10th day, the leaves have fully opened up. You can also see that the stem of the bean plant had gotten much thicker and sturdy.
Finally, on the 13th day, we took the bean plants out of the bag to study them closer. The bean seeds had grown into young plants and you can see that additional leaves had started growing out of the stem.
The roots were embedded in the paper towel and we couldn’t separate them without breaking the roots. When we flipped over the paper towel, we could see just how long the roots had gotten. The roots of the four bean plants were so intertwined that we could barely tell which root system belonged to which plant.