The Effect of Water Moisture and Worms on Plant Growth Researched by Glynnis O. 1999-2000

PURPOSE

The purpose of this experiment was to determine the effect of soil moisture on the growth of beans.  In addition, I determined the effect of earthworms in the soil on bean growth.

I became interested in this idea when my family’s corn did not grow very well in our garden in Colorado almost every year.

The information gained from this experiment can be used to help farmers living in areas of low rainfall, to learn how to keep their plants alive.

HYPOTHESIS
My first hypothesis is that the bean plants with the earthworms will grow taller.    My second hypothesis is the group with the 100 mL of water will grow higher.

I base my hypotheses on information collected from textbooks, the Internet, and some CD-ROM’s.

EXPERIMENT DESIGN
The constants in this study were:
•  amount of soil in each pot
•  size of the earthworms
•  how many seeds are planted in each pot
•  the type of pot
•  size of the pot
•  how much water is used in each pot every time
•  the amount of light
•  the depth the seeds are planted
•  the amount of compost
•  number of worms
•  soil compactness

The manipulated variables are the amount of water and whether earthworms were in the soil added to each pot.

The responding variable was the growth of the bean plants.

To measure the responding variable I held the plant outstretched in the pot and measured the plant in centimeters.

MATERIALS
 QUANTITY ITEM DESCRIPTION 18 Whole lima beans 5,400 mL Tap water 6 Plant pots 1,320 g Potting soil 12 Earthworms 1bottle "Schlutz Plant Food" 1 Bucket that can hold 1,000 mL 1 Measuring cup

PROCEDURES

1. Place 220 g of potting soil in each of the six pots.
2. Label the first three pots as follows: Dry with worms, Wet with worms, and
ì Wettest with worms.
3. Label the others as follows: Dry, Wet, and Wettest.
4. Place four earthworms in the Dry with worms pot, four earthworms in Moist with worms, and four worms in Wet with worms.
5. Then poke three two centimeter, in length, width , and depth, holes in a triangle , in the middle of the container , with either your finger or pencil in all six pots.
6. Drop one lima bean in the holes in the pots.
7. Cover the seeds with the soil dug out from the holes.
8.Pat the soil down with your hand three times.
9.Get a bucket that holds 1,000 mL.( This is what you’ll use when watering the plants.)
10. Pour about1,000 mL into the bucket.
11. Add 7 drops of Schlutz Plant Food.
12. Water the Dry pots with  50  mL .
13. Water the Moist pots with 100   mL
14.  Water the Very Wet pots with 150  mL.
After seeds are planted:
15. Water the plants the exact same amount of water, you did the first time you watered the plants, every day.
16. Make notes of how much the controlled plants grew, and how much the plants with the earthworms grew, right after you watered the plants.
17. After at least three sprouts are up, start rotating the pots one quarter turn.

RESULTS
The original purpose of this experiment was to find out if earthworms added to the soil would make the bean plants grow higher and stronger.

The results of the experiment were that the average height of the plants of the "Moist"(100 mL) groups was greater than any of the other groups. The groups with the least amount of growth were the “Very Wet” groups.

According to the data collected from my experiment, the worms must have helped because the plants in “Dry with worms” (50 mL) grew rather high even though it had a lack of water. The other groups with worms also grew higher even if the pots had too much water or just the right amount of water in the pot.

CONCLUSION
My hypothesis was that the bean plants would grow higher with more earthworms added to the soil.

The results indicate that this hypothesis should be accepted, because the plants in the pots with worms seemed to grow stronger and better.

Because of the results of this experiment, I wonder if the season, even if they were inside a house, would affect how the plants grew.

If I were to conduct this project again I would have written more detailed notes to give the reader a better picture in his/her mind. I also would have taken more pictures of the root systems after we took them out of the pot. The last difference I would make would be to make sure that the plants all got the equal amount of light.

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