
Root Growth and Moisture Direction
Medium
Do plant roots grow toward the nearest source of water? You plant green beans in three pots. Each pot has a porous cup buried in the soil. Pot A gets water only through the porous cup. Pot B gets water through both the cup and the soil. Pot C gets water only in the soil.
After 10 days, you remove the plants and check the root direction. In all three pots, the roots grow straight down instead of sideways toward the porous cup.
Hypothesis
The hypothesis is that the roots of a germinated green bean will grow towards moisture.
Method & Materials
You will need to fill 3 gardening pots with soil, plant 10 green beans in each pot, and water the pots daily for 5 days. Then, fill the porous cups in two of the pots with water and water the soil in the other pot for 10 days. After 10 days, remove the plants from the soil and observe how the roots have grown.
You will need 1 packet of green beans, 3 gardening pots, soil, a gardening spade, tap water, 3 porous cups, and a black marker pen.
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See what’s includedResults
The results showed that the roots in all 3 pots grew straight down, not towards the porous cup. This disproved the hypothesis that the roots of the germinated green bean will grow towards moisture.
Why do this project?
This science project is interesting because it explores how plants respond to water in soil, and if they can sense where the water is located and start to grow towards it.
Also Consider
To vary the experiment, try using different types of seeds like corn seeds or soy beans. You could also repeat the experiment over a longer period of time to observe if the direction of root growth will change as the soil becomes drier.
Full project details
Additional information and source material for this project are available below.Related videos
These videos explain the science behind this project and demonstrate key concepts used in the experiment.
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