the effect of the amount of compost on the growth rate of a round pea seed

Isabella V. Jimenez2011 Young Naturalist Award

Isabella Jimenez Grade: 7 Lab ReportTITLE:The Effect of the Amount of Compost on the Growth Rate of A Round Pea Seed.

INTRODUCTION:My interest in planting began with a bean experiment in kindergarten.

I vividly remember wrapping a kidney bean in a moist paper towel and placing it in a clear zip-lock bag. Along with my twenty-four other classmates’ experiments, I then taped my bag to the window in my classroom. Observing the growth of the bean plant daily fascinated me and encouraged me to repeat the same experiment with my family at home.

Since then, I have continued to plant every spring. I planted tomatoes, peppers, and beans in a pot because we lived in a townhouse. In second grade, my family moved to a single-family house with more than an acre of land. When I looked out from the deck, all I saw was fertile land just waiting to be dug up! My first spring was an adventure. I planted cucumbers, beans,

peppers, berries, and many herbs. I noticed that my yard had different quality and color of soil. I initially thought that the color difference was due to the amount of sunlight the ground received. I asked my parents and grandmother to explain my observations and interpretations, and learned that the darker, softer soil was due to the leaves that had decomposed over time in certain areas of the land. I also learned that plants need nutrients and compost as a natural source of food for plants.

I have since begun reading books on organic gardening and composting. Composting is the process of breaking down organic materials such as grass lawn clippings, leaves, and other biodegradable components by microorganisms like bacteria and fungi. I started my first compost bin that same year. I collected fruit and vegetable peels and skins and placed it in the compost bin that my dad and I made in the far back of the yard. Every spring I ask myself if adding more compost would increase the growth of my plants. I guess if compost contains nutrients that plants need, then increasing the amount should also increase the growth of the plant. But the tough question is, “ How much is too much?” It’s almost like eating food which is good for us because it helps us grow, but if we overeat this could lead to health problems.

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This level of curiosity lead me to conduct my experiment using different amounts of compost (from my compost bin) to observe the effect on the growth of round peas. This experiment was conducted to show and evaluate the effect of the amount of compost on the rate of growth of a pea plant. I wanted to gather the data from this experiment and use the results to make me a better organic farmer and share it with my community. This information could be useful to my community because a lot of people where I live enjoy planting in the spring and summer.

I hoped to see a difference between the experimental trials. I wanted to see that the compost really did help to change the growth of a pea plant. Also, I wanted to learn if recycling old fruits, vegetables, leaves, grass cuttings, and even old coffee grinds could let a plant grow faster. I thought that if the amount of compost is increased, then the growth of the plant will also increase.

EXPERIMENTAL DESIGN DIAGRAM:Question: What is the effect of the amount of compost on the rate of growth on a pea plant?

Hypothesis: If the amount of compost is increased, then the rate of growth of the pea plant will also increase.Independent Variable (I.V.): The amount of compost.Levels of I.V.

Store bought soil. + 0 Tbs. compost(CONTROL)

Store bought soil. + 1 Tbs. compost



Repeated Trials per Level

6 6 6 6

Dependent Variable: The Rate of Growth of the Round Pea plant.

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Isabella V. Jimenez2011 Young Naturalist AwardConstants:

1. Store-bought soil (1 cup)2. Water supply (1 Tbs. per day per trial)3. Round Pea seed (24 total)4. Clear plastic solo cups (24 total)5. Sunlight

Materials List: 1. Round Pea seeds (24)2. Store-bought soil 3. Home-made organic compost4. Water5. Metric ruler 6. Clear plastic solo cups (24)7. Muffin Pan 8. Latex gloves9. Toothpick10. Ceramic cup 11. Sharpie12. Measuring cup and spoon (1 Tablespoon/Tbs)13. Digital Camera 14. Nail

PROCEDURE & METHODS:1. Using a nail, 2 holes were punched in the bottom of 12 solo plastic cups2. The solo cups were placed in each of the muffin pan spaces. 3. A Sharpie was used to label each cup with its correct amount of compost.4. One (1) cup potting soil was placed in each solo cup.5. The correct amount of compost was added to each solo cup.6. A toothpick was used to poke two holes in the soil of each solo cup.7. Next a pea seed was placed in each of the two holes in each solo cup.8. The ceramic cup was filled with tap water and poured 1 Tbs. of water in each solo cup every day.9. A metric ruler (cm) was used to measure the plants when there was at

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Isabella V. Jimenez2011 Young Naturalist Awardleast one plant growing per level of compost. That is, when I could see at least one plant sprouting in each i.v. level. This was recorded as day #1. Plant height was measured to the nearest tenth decimal place. Measurements were done daily at 3 p.m.

RESULTSKEY: L = left plant height (cm) R = right plant height (cm)

Day # 1Date CONTROL 1 TBS Compost 2 TBS Compost 3 TBS Compost01/09/11 L R L R L R L RExperiment #1 Row

0.0 1.2 0.8 2.1 0.0 0.0 3.0 1.5

Experiment #2 Row

0.0 0.0 0.0 0.0 4.6 0.0 0.2 1.0

Experiment #1 Row

Experiment #2 Row

Experiment #3 Row

0 TBS Compost(control)

1 TBS Compost 2 TBS Compost 3 TBS Compost

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Isabella V. Jimenez2011 Young Naturalist AwardExperiment #3 Row

0.9 2.2 2.0 0.5 0.0 0.4 0.4 0.0

OBSERVATIONS: Water-logging in all control containers.


0.0 1.8 1.7 3.0 0.0 0.5 5.5 4.0

Experiment #2 Row

0.0 0.0 0.7 0.2 8.0 0.0 1.1 2.0

Experiment #3 Row

1.9 3.2 3.4 1.0 0.0 1.2 1.1 0.5

OBSERVATIONS: The tallest plant is in the 2 Tbs compost level. 100 % of the plants with 1Tbs & 3 Tbs compost show growth. 50 % (3/6) of the control trials and the 2 Tbs compost show no

growth.


0.0 3.6 3.3 6.0 0.0 2.0 11.0 7.8

Experiment #2 Row

0.0 0.0 2.5 1.0 14.0 0.0 3.0 5.1

Experiment #3 Row

3.4 6.1 5.5 2.7 0.0 2.6 2.7 2.1

OBSERVATIONS: In experiment # 2, the tallest plant (14.0cm) is in the 2 Tbs compost and there is no growth (0.0cm) in the other seed in that same trial.

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0.0 5.2 5.3 10.0 0.0 3.5 15.3 12.5

Experiment #2 Row

0.0 0.0 4.2 1.7 16.0 0.4 4.6 7.5

Experiment #3 Row

6.0 11.0 9.0 4.0 0.0 4.2 3.7 3.2

OBSERVATIONS: 50 % of the control trials show no growth. 33% (2/6) of the 2 Tbs trials show no growth. New growth (0.4cm) in the 2 Tbs trial with the tallest plant


0.0 10.2 11.5 15.0 0.0 6.0 20.0 18.5

Experiment #2 Row

0.0 0.0 9.0 4.0 22.2 1.3 7.0 14.0

Experiment #3 Row

11.2 14.5 15.5 7.5 0.0 9.5 6.5` 6.5

OBSERVATIONS: The tallest plant (22.2cm) continues to be in the 2 Tbs compost trial (the second set of experiment).

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0.4 14.5 16.7 20.5 0.0 10.7 25.2 23.5

Experiment #2 Row

1.0 0.0 9.0* 7.5 26.2 3.3 11.5 19.0

Experiment #3 Row

16.0 19.0 18.3 12.4 0.0 13.5 10.0 11.4

OBSERVATIONS: *plant broke (I kept the height as 9.0cm)


2.2 18.0 22.1 26.0 0.0 15.2 31.5 27.5

Experiment #2 Row

1.5 0.0 9.0* 11.5 29.2 6.3 16.6 24.0

Experiment #3 Row

22.0 24.2 24.5 17.3 0.0 19.0 14.0 17.0

OBSERVATIONS: The tallest plant (31.5cm) is now in the 3Tbs compost trial.

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Isabella V. Jimenez2011 Young Naturalist AwardRESULTS:

Data Table Showing Daily Average for Each Level of I.V. (:- Amount of Compost)Key: SBS = store bought soil

Independent variable

Type of soil

DV Day

1

DV Day

2

DV Day

3

DV Day

4

DV Day

5

DV Day

6

DVDay

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Growth Rate

(cm/day) 1 cup SBS + 0Tbs compost

0.71 1.15 2.18 3.70 5.98 8.48 11.35 1.62

1 cup SBS + 1TBS compost

0.90 1.60 3.50 5.70 10.42 12.56 16.90 2.90


0.83 1.61 3.10 4.02 6.5 8.95 11.61 1.66


1.01 2.36 5.28 7.80 12.08 16.78 21.76 3.1

GRAPHS:See pages 15 -196. ANALYSIS AND INTERPRETATION:

During the course of my experiment, I observed firsthand the benefits of using compost to sow. Pea plants with 3 tablespoons of added compost grew at the fastest rate. The trials with no added compost showed the least growth. I also saw that the ability of the soil to retain the appropriate levels of water was better as the amount of compost material was increased. The trials with no added compost showed a significant amount of water-logging. This data compliments the information that I previously researched on the importance of composting. Compost can enrich soil in many ways such as increasing the amount of nutrients, improving drainage and airflow, while improving soil texture.

My findings in this experiment are quite important, because they show that just by using compost, the pea plant can grow faster. This information affects my own life and others life by helping our planet grow cleaner and greener through an easy process of recycling. Since there are

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Isabella V. Jimenez2011 Young Naturalist Awardmany people in my community, I can teach them about a simple and easy way to reduce trash in landfills and use the compost that they make for planting.

At the end of my experiment, I reviewed the collected data and asked myself why there was not a proportional increase between the amount of compost and the rate of growth of the plant at each level. For example, the rate of growth for the control trials with no compost was 1.62 cm/day and the rate of growth for the trial with 2 tablespoons of compost was 1.66 cm/day. The level with 2 tablespoons of added compost showed the widest range (0 to 29.2 cm) of plant height. By eliminating outliers such as not including plants that did not grow would help reduce sources of error.

CONCLUSION:The purpose of the experiment was to evaluate the effect of the amount of compost on the rate of growth on a round pea plant. This experiment supports my original hypothesis that if the amount of compost is increased, then the rate of growth of the pea plant will also increase. Even on a small scale, compost material seems to have a positive impact on plant growth due to the many ways in which it improves the soil. This project has led me to think of designing a new experiment where I will keep the total amount of soil and compost at a constant. This would decrease the amount of variability and the possible confounding factor of soil quantity. I plan to carry out this experiment on a larger scale with my girl scout troop. This time I will use different amount of compost material on my garden beds and count the number of cucumber that are produced on each level of the independent variable (:- the compost material). This project will encourage me to continue to plant and make good use of my compost.ACKNOWLEDGEMENTS:I would like to thank my science teacher Mrs. Roache-Buchanan for encouraging scientific curiosity, teaching me research methods, and inspiring me to participate in The Young Naturalist Awards.BIBLIOGRAPHYBeckett, Ken, Noel Kingsbury, and Tim Newbury. Gardening Basics. New York: Sterling, 1999. Print.Holden, Patrick. The Gaia Book of Organic Gardening. New York: Gaia, 2005. Print.

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Isabella V. Jimenez2011 Young Naturalist AwardHttp://www.fairfaxcounty.gov/parks/gsgp/infosheets/maintenance.pdf. Web. 24 Feb. 2011

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http://www.fairfaxcounty.gov/parks/gsgp/infosheets/maintenance.pdf

http://www.fairfaxcounty.gov/parks/gsgp/infosheets/maintenance.pdf


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Me at my compost bin 2011Round pea box and peas

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My tomato treeMy organically grown cucumbers 08/2008

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the effect of the amount of compost on the growth rate of a round pea seed

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