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We received the following science project from Sydney, a fifth grader who wanted to research the effects of different diets on plant growth. In her tests, she used Extreme Juice as well as an assortment of other diets... Read on to find out her results!

Too Much of a Good Thing?
by Sydney W.
Grade: 5

Statement of Purpose

I wanted to determine the effects of different nourishments (liquid diets) on plant growth. I was interested in learning what makes plants grow best. I thought the results might also apply to human diets.

I expected a healthy diet would be best for the plants. I assume the plants that are fed plant food will grow better than non-plant food diets.

Hypothesis

I predict that out of all the diets, No diet, Tap water, Milk, Coke, Sugar water, Tea, Extreme Juice (natural plant food), and Miracle-Gro (synthetic plant food) that Extreme Juice will be the best out of all of them because it is all organic.

Research

To understand how these different diets might affect plant growth, you need to understand how a plant grows.

Plants grow and get food from two processes, photosynthesis and respiration. These processes make food in order for the plant to grow. Plants need water, mineral salts, and food such as carbohydrates. Green plants may take in food from decaying plants and animals, or directly from other living plants. Most plants need sunlight and water to grow. Some plants that live in the ocean get no sunlight but get their vitamins and minerals from the water only. On land, plants need oxygen and carbon dioxide.

The plants starts off as a seed and then slowly grows into a seedling. The seed is protected by the seed coat. The embryo is located inside the seed. The embryo is what grows into the plant. In the beginning, the embryo lives off the food supply in the seed. The embryo then turns into a seedling and grows roots.

Roots grow downward because they can detect the pull of gravity. The root responds to gravity by releasing chemicals that cause more growth on the upper side which causes the root to turn downwards. The growth on the upper side is called a shoot. Most shoots grow upward toward the sunlight. The growing tip of the shoot can detext the direction of the light and chemicals are released that make it grow more on the lower or darker side. This turns the shoot upward.

The shoot then sprouts leaves that the plant uses to make food. Green plants make their own food in a process called photosynthesis. Chlorophyll, the green pigment in plants, helps to trap energy from the sun. Plants use this energy to convert its food, water and carbon dioxide into sugars.

Plants use their extensive root systems to take in water and minerals from the ground. Each root branches into a network of rootlets which in turn grow root hairs. The water and minerals pass into the root across the cell walls of millions of tiny root hair.

Knowing this, I am curious to see how the plants respond to the different fluids.

Materials

I was thinking about what diets I would feed each plant. In talking with my teacher, Miss Curtain, she suggested a milk diet. Accordingly I added milk to my diet list.

I also called the Garden Guy (Dave Owens) from Channel 3 T.V. I wanted to know what types of plant food was available and the best plants to use, based upon the amount of time we had for this science project.

The plants- Zonal Geranium Eight Geraniums were purchased from the same batch at the store, so that they would all be the same.

The Diets-

1. Plant number 1 was to receive no nourishment or liquid. No diet was chosen for this plant to serve as a control group or plant. The control plant helps show the differences in the diets versus nothing being done. The no diet plant and plain water plant are comparable to a control group or placebo group in human experiments. You use these plants or group to contrast the other diets effects.
2. Plant number 2 was provided plain tap water.
3. Plant number 3 was provided milk.
4. Plant number 4 was provided Coke.
5. Plant number 5 was provided sugar water.
6. Plant number 6 was provided black tea with water.
7. Plant number 7 was provided Extreme Juice (natural plant food) mixed with water.
8. Plant number 8 was provided Miracle-Gro (synthetic plant food).

Other Materials-

1. Measuring cup, 1 cup in size.
2. Ruler to measure plants.
3. Marker and labels to label the plants.
4. Notebook to record weekly results.

Procedures

I started my science project on January 23, 2004. The plants were purchased and measured before the diet was started.

1. No diet - 10 inches
2. Tap water - 11 inches
3. Milk - 10 inches
4. Coke - 9 inches
5. Sugar water - 11 inches
6. Tea - 10 inches
7. Extreme Juice - 11 inches
8. Miracle-Gro - 11 inches

The most important procedure of any experiment is to keep everything the same, except for the one item you are testing.

In my project the item I tested was the different liquids or diets. The only difference in the core of these plants was the diet of each plant.

The plants were kept together so they would always receive the same amount of light and temperature. One cup of each liquid diet was provided to each plant every four days.

I used two percent milk, room temperature Coke. Three tablespoons of sugar was added to one cup of tap water. One ounce of Extreme Juice and one ounce of Miracle-Gro was added to one cup of tap water for the plant food diets. One cup of black tea was used for the tea diet.

The plants were taken outside every morning at 8:00 a.m. The plants were placed in the sun each morning. If it looked like it could rain the plants were kept outside under a patio cover. The plants were brought inside the house each evening at 7:00 p.m.

Observations

The plants were looked at each day as they were placed outside and brought in each night. After seven days the no diet plant started to show signs of dryness. The leaves became smaller and somewhat discolored. Some leaves started to die.

Also after 7 days the milk diet plant was not growing and the leaves actually got smaller. This difference can be seen in the starting pictures and the ending pictures.

The Coke and sugar water plants after seven dats also was not getting fuller growth. The tea leaves were getting darker.

After seven days the Extreme Juice diet was showing the most growth and bud production. As a surprise to me the Miracle-Gro plant was not growing and seemed to be dieing.

I measure the plants at several different times: I measured from the base of the pot to the highest point on the plant.

In addition to the measurements the following observations were made:

2-15-04

1. No diet - Appears very wilted and dry. The diameter is smaller.
2. Tap water - Seems healthy. A couple of leaves are brown.
3. Milk - No growth. Leaves are smaller than when started. Leaves are brown and yellow. Has a sour odor.
4. Coke - Doing well. Starting to sprout buds and flowering.
5. Sugar water - Buds are appearing. Leaves appear to have bigger diameter then other plants. Leaves starting to change color.
6. Tea - Leaves are now darker than other plants. Appears healthy.
7. Extreme Juice - Very healthy. Has grown full blossoms and has clusters. Only plant with full flowers.
8. Miracle-Gro - Dead leaves. Plant is wilted and discolored. Plant appears to be shrinking and not as full as other plants.

Conclusions

I believe that my hypothesis was proven in part and disprove in part. The one plant that was provided Extreme Juice (natural plant food) did better than the other diets. The one plant that was provided Miracle-Gro (synthetic plant food) did worse than almost all of the other diets. Based upon my experiment, natural plant food was best for these plants.

I believe that organic or natural plant food is better than any other diet for plants. We also hear this is true in the news media, when it comes to organic food for humans.

Several items might need to be looked at further to explain the results of the experiment. Was the Miracle-Gro plant healthy to begin with? Was the Miracle-Gro plant food mixed too strong for such a small plant? Additional experiments would need to be done to see if you obtained the same results.