The Effects of Extreme Water Temperatures on Basil

Natalie Mendoza
Ms. Lammart
Honors Biology
15 October 2020

The Effects of Extreme Water Temperatures on Basil:

BACKGROUND:
Ocimum basilicum, commonly known as basil, is a plant that grows best with six to eight hours of direct sunlight per day; moist, water absorbing soil; and frequent watering (Schalau, 2009). Additionally, basil grows well in hotter environments like Central Arizona. This paper will look at how sprouting and watering basil with extreme water temperatures will affect germination and growth.

HYPOTHESIS:
If basil plants are watered with 200 degree Fahrenheit water, then the basil plants will grow taller than basil plants that receive 76 degree Fahrenheit water or 40 degree Fahrenheit water, because basil grows taller in hotter environments, so watering basil plants with hotter water will result in more growth.

PROCEDURES:
In this section, the materials, steps, and experimental groups used to conduct this experiment will be documented.

MATERIALS:
>> Basil seeds
>> Soil pods
>> Bio-domes
>> Graduated cylinder
>> Water dropper
>> Thermometer
>> Ruler

STEPS:
1. Label the basil bio-domes with the water temperature the basil plants will receive.
2. Soak the soil pods in the appropriate temperature water for each bio-dome.
3. Plant 9 basil seeds (three for each experimental group) ⅛ inch deep into the soil pods.
4. Set the basil bio-domes in direct sunlight (indoors) for at least 7 hours (from 9:00 AM to 4:00 PM) and leave them indoors at night.
5. Water the basil every week with two drops of water from the water dropper for each soil pod/basil plant.
6. Fill a beaker with water.
7. For each group, make the water the correct temperature.
Heat the water in a microwave oven to 200 degrees Fahrenheit.
Chill the water in a freezer to 40 degrees Fahrenheit.
Leave the water on a counter at 76 degrees Fahrenheit for ten minutes.
7. Take the water’s temperature with a thermometer after ten minutes. If it is the correct temperature (40 degrees Fahrenheit, 76 degrees Fahrenheit, or 200 degrees Fahrenheit), proceed; otherwise, continue heating or cooling until the water is the correct temperature.
8. Water each soil pod or basil plant (after the seed sprouts) with two drops of water using a dropper.
9. Keep track of when the seeds sprout.
10. After the three week experimental period is over, measure the height of the basil plants in centimeters.
11. Aggregate and graph the results for each group.
12. Analyze results and draw conclusions.
13. Publish and share my research.

EXPERIMENTAL GROUPS:
>> Basil plants watered with extremely cold (40 degrees Fahrenheit) water
>> Basil plants watered with a constant (control) 76 degrees Fahrenheit water
>> Basil plants watered with extremely hot (200 degrees Fahrenheit) water

VARIABLES:
The independent variable is the temperature of the water. The dependent variable is the height of the plant. The control variables are the amount of sunlight, the amount of water, and the soil type.

SAFETY PRECAUTIONS:
It is unlikely for there to be safety issues in this experiment. To prevent the 200 degrees Fahrenheit water from burning me or 40 degrees Fahrenheit water from freezing me, I will leave room at the top of the container so the water does not accidentally slosh over and spill. Additionally, I will not touch the hot/cold water directly; instead I will use a dropper to move the water to and from the plants.

PICTURES:
Before:

40 degrees Fahrenheit
Extreme Cold Water Group
76 degrees Fahrenheit
Control Water Group
200 degrees Fahrenheit
Extreme Heat Water Group

After:

40 degrees Fahrenheit
Extreme Cold Water Group
76 degrees Fahrenheit
Control Water Group
200 degrees Fahrenheit
Extreme Heat Water Group

RESULTS:
A chart with the results is linked below:
https://docs.google.com/spreadsheets/d/1SSnviUE_p24ecQAczZppM7uAoxRze59FNy4loJEG-4M/edit?usp=sharing

Each white dot represents the final height of one of the basil plants. The three black diamonds represent the average final height for each water temperature group.

ANALYSIS:
The basil plants in the Extreme Cold Water Group that were watered with 40 degree Fahrenheit water did not grow well. Five of the twelve basil seeds in this group did not sprout at all and the basil seeds that did sprouted two days later than the others. The average height of the Extreme Cold Water basil plants was 1.61 cm. Additionally, whenever the 40 degree water was placed on each of the soil pods, it formed a half-state between water and ice.
The basil plants in the Control Group that were watered with 76 degrees Fahrenheit water had the most growth of all of the groups. All of the twelve basil seeds sprouted, and grew an average of 3.28 cm.
The basil plants in the Extreme Heat Water Group that were watered with 200 degree Fahrenheit water fared better than the 40 degree watered plants, but worse than the plants that received 76 degrees Fahrenheit water. One of the basil seeds did not sprout at all and the basil plants grew around 2.73 cm on average. Additionally, the soil pods were more matted down than the soil pods that only received 76 degree Fahrenheit water.

CONCLUSION:
I conclude that basil plants should not be watered with extreme temperatures. My hypothesis that the basil plants watered with 200 degree Fahrenheit would grow taller than basil plants watered with 40 degree Fahrenheit or 76 degrees Fahrenheit water was proven false. If I were to repeat my experiment, I would use slightly less extreme temperatures. The basil plants that I subjected to extremely cold temperatures, (the ones that actually sprouted), look frail and ghastly, and it will take a lot of work to heal them. I feel horrible that I caused their unhealthy, fragile state. I am confident that this experiment violated ethical codes because I caused the basil plants in the extreme cold experimental group to fail to thrive. I will continue to care (and heal) the basil plants indoors until they grow large enough to transplant them into a garden outside in late February or March, when the temperatures are warmer.. In future experiments, I will not endanger plants’ health by altering plants’ growing conditions. While I am still passionate about science, I do not wish to cause further harm to plants. In the future, I plan to experiment on evolution – specifically on bacteria because of how quickly bacteria can reproduce.

Works Cited:
Schalau, J. (2009, Jul, 08). Growing Basil. Backyard Gardener Retrieved from
https://cals.arizona.edu/yavapai/anr/hort/byg/archive/growingbasil.html