Data Cycle #17 (Do Seeds Need Soil?)

Experimental Design

By Mrs. BensonVoss

Do seeds need soil in order to germinate?

Mrs. Perry, Mrs. Benson, and Mrs. Voss recently tried to grow some lima beans in bags in front of the window between our classrooms.
3 of the seeds were watered but did not have soil.
3 of the seeds were watered and did have soil.

Multiple Choice

The independent variable is the thing that "you" are purposefully manipulating (changing). What is the independent variable in this experiment?

• the water

• the sunlight

• the soil

• the space

Multiple Choice

The dependent variable is what you are "measuring" to see if your changes are making a difference. What is the dependent variable in this experiment?

• The number of seeds that sprouted.

• The amount of water in each bag.

• The type of bag the beans are in.

Multiple Select

Constants are all of the materials and situations that are the same, to keep the experiment valid. What are the constants in this experiment?

• water

• soil

• sunlight

• bags

Multiple Choice

What is the control?

In this case, you must think about what plants, or seeds, normally get in order to live.

• The plants with the soil are the control.

• The plants without the soil are the control.

• There is no control.

Conclusion

After 7 days, one of the seeds in water had sprouted and all of the seeds in soil had sprouted.
After 9 days, all of the seeds in water had died but all of the seeds in the soil had sprouted.

Conclusion: No, seeds do not need soil in order to sprout, but they do need nutrients.