Winter is a time when most plants stop growing. Some plants die when the weather is too cold, but leave seeds behind to germinate — begin growing — when the temperature is right. This is the nature’s way of ensuring that species survive cold weather.
Materials for this Science Project are Basic
This project is intended for elementary students. The material list is short and includes:
- lima bean seeds — buy seeds intended for planting since they are treated to prevent fungus which could interfere with the results. Kidney and pinto beans work well, too.
- two Ziploc-type sandwich bags that can be resealed
- two paper towels folded to fit in the sandwich bags — they should be the same shape as the bag and just small enough to fit inside
- a thermometer
- a three panel poster for the display
The Science Project Procedure
This experiment works best in cool weather since a cool place — below 60 F is needed.
- Fit one paper towel into each plastic bag — it should be several layers thick after folding.
- Pour enough water into the bags to wet the paper towels. Pour extra water out so that the towel is damp, not dripping wet.
- Place three seeds in each bag. Three seeds will ensure germination of at least one or two — perhaps all.
- Seal each bag.
- Decide on a location in the house that is warm. Temperatures from 65 F to 75 F work well — a bit warmer is better. The temperature can be verified with the thermometer.
- Find another location where the temperature is at least 20-25 degrees cooler than the location for the warm bag — garages often work well. It should be kept at a temperature from 50 F to 60 F.
- Check seeds daily to see if they have spouted. Record results with dates. The warmer beans should sprout first. The exact time will depend on temperature.
- Place two seeds in each bag and place each on a flat surface seed-side-up where they will not be disturbed. Light is not needed for germination, but will be needed after germination for the plant to continue to grow, although continued growth is not part of the experiment.
Students may need to modify the procedure according teacher rubrics or instructions. Also, variations of this investigation are available.
Science Project Results
The seeds kept in the warmer location should sprout sooner than those in the cooler environment. Germination in the warm location should occur in a week or less if temperatures are in the low 70s. The seeds in the cool location may require twice as much time.
After germination, unseal the bags and prop the open end up two or three inches. This will encourage the plants to grow upward toward the opening. Add water to keep the paper towel damp as needed. The seeds will swell as they absorb water, but this is not germination.After several days, the new plants will need bright light to grow. Sunlight is best, but artificial light will work for the length of the experiment.
Follow the growth of the seeds for a week after the first of the “cool” seeds germinates, taking brief notes on the progress of all seeds — height, number of leaves, any signs of disease.
Germination is the day on which any part of the plant — root or leaves — is visible. Data can be displayed comparing the “warm seeds” with the “cool seeds.” A simple bar graph can have days on the horizontal axis and the number of seeds germinated on the vertical axis. Mark the dates of germination with different colors, symbols, or stick-on stars using different colors or shapes for each group of seeds.
Using the Scientific Method for The Science Project
A review of the scientific method is a good idea. For elementary students it is usually sufficient to state a hypothesis, describe the procedure, state a conclusion, and communicate results using the display poster.
The hypothesis should be an “If… then…” statement — e.g., “If lima beans seeds are planted and placed in different temperatures, then the beans planted in the warmer location will sprout first.” The independent variable is what the student controls — in this case it is temperature. The dependent variable is the result of changing the temperature — time required for germination.
Photographs of bean development will be a nice addition since the plants likely will have died before the science fair.
Plant Science project allows the collection of data on living things. Changes can be observed each after the plants have germinated. Temperature is a main factor in germination. Investigating how seeds germinate in different temperatures makes an easy science project that is easily managed.
Sources:
"NSTA.org, SciLinks.org, and Other NSTA Resources," (Accessed October 26, 2011)
Harvey Craft - I am a retired educator with diverse experience. I read anything science, education, and history. I write to share what I learn.
