How Does the Colour of Light Affect the Growth of a Plant and Which Light Is Best

How does the colour of light affect the growth of a plant and which light is best

The problem will be investigated is how does colour of light affect the plant growth and what colour is best in terms of speed of the growth of the plant

By using the internet I discovered that the problem that I am trying to solve has been done before by various people. As I read the information given off the web it seems that plants that can only absorb certain types of colour of light for example blue or red. But as the colours change it causes a different effect to the plant in terms of its growth.
I also found that plants in their natural habitats get this different shades of light form sunlight. According to mocomi.com, and WA KKG a member of yahoo answers sunlight might see yellowish but actually contains seven different colours all of which make up the rainbow. When light is separated it displays seven colour which consist of red, orange, yellow, green, blue, violet and indigo. Red is known to bend the most and indigo the least. This colours can been seen yourself if a glass prism is held up in the air so sunlight can pass through and causing it to bend showing the colours.
The final thing I learnt while researching is that blue and red light is what plants absorb. Blue light is responsible for the vegetative growth (leaf growth). Red light when combined with blue light encourages flowering. And plants only look green only because they reflect green rather than absorb it.

Each colour will have a different effect on the plant growth and that the translucent light will be best in terms of the growth
The experiment that will be conducted will test the effects of a plant when it receives different colours of light and in the end showing which one is most effective in making it grow. The experiment will use various colours of light for example blue, red, translucent, green, ect. These different shades of light will not be in the same area as each other in order to receive precise results. One plant will be placed with each coloured light. All plants will receive the same amount of food and water so the only changing variable will be the light. The plant growth will be recorded every 2 days. The recorded information will consit of the height of the plant and the leaf count of the plant.

The independent variable in this experiment that I will be conducting is the colour of the light. The colour of the light for each plant will change in order to receive multiple results and to see the effects of what happens when a different colour of light is shun of on a plant. Each plant will have its own colour of light shun upon it. The colours that will be shown is any one of the colours that sunlight consists of.

The depent variables in this situation will be the height of the plant and the leaf count of the plant. The method on how to do so is simple and accurate. Each two days a ruler will be held against the plant and height of the plant will be measured and recorded. A leaf count will also be held whilst the measuring is taken place. A leaf count is a counting of how many leafs appear visible on the plant allocated. Once counted the results will also be recorded within a graph.

Water….it could affect the experiment by screwing up the results as one will receive more water than the other causing it to grow better than the others or worse than the others….it will be controlled by giving the same amount of water to each plant using a measuring cup so the water won’t cause and difference to plant the compared the others

Brightness of the light….it could affect the plant as one might receive a brighter light then the others which could make it dehydrate easier than the rest of them or enhance the growth due to the light brightness or even burn it the plant….it will be controlled by only placing lights that produce the same amount of volts and brightness

Battery of the light duration….The battery that is within the light can affect the results as one light might run out of power which will cause the light to go off and cause the plant to stop growing while the others continue….The battery situation can be controlled by using lights that can be connected to a power point so that the lights can receive endless power
Closeness of the light…. The closeness of the light could affect my experiment my allowing one plant or group of plants the receive stronger light as a result of it being closer than the others….it can be controlled by allowing all lights be the exact same length apart from the plant so that if one gets a stronger light due to closeness they all get it as well

Type of soil…. The type of soil can have a big impact on the experiment as one soil might contain high quality manure where another might have a not so good quality manure within the soil….for it to be controlled all plants will receive the same type of soil so no their will be no chance of change in soil quality

The equipment that will be needed to conduct the experiment will consist of: * 5 boxes * 15 clear cups * 1 red light * 1 blue light * 1 green light * 1 yellow light * 1 clear/normal light * 15 _____ _____ seeds * Potting soil * Tap water * Ruler * Measuring cup

The experiment will be done and conducted like this: 1. Place potting soil onto clear cup 2. Dig a small hole on the side of the clear cup 3. place one _____ ____ seed into clear cup making sure its visible form the out side 4. Cover the seed with the soil dug out of the hole 5. Look to see whether seed is visible form out side 6. Repeat steps one to 5 for all the remaning clear cups 7. Pour tap water onto all of the plants using the measuring cup 8. Make sure all plants receive the same amount of water 9. Place cups into groups of three 10. Place each group of three into one box 11. Place one of the coloured lights into each box 12. Close box 13. Turn all coloured lights on for three hours 14. Turn all coloured lights off for three hours 15. Pour tap water using the measuring cup onto all of the plants every day 16. Record measurements every 2 days using the ruler 17. Repeat steps twelve, thirteen, fourteen and fifteen

Touching bulb whilst hot…. It can be avoided by only grapping the bulb after five minutes has passed after the switching of the bulb

Spilling water on light causing electric shock…. Can be reduced by being care full when pouring water onto plant and making sure that no one is next to you whilst pouring water

light catching fire when on for all day…. The issue can be reduced by only allowing the lights to be on for three hours straight and allowing it to rest for the next three hours so that it can be turned on after

The results that I will record will consist of having the length of the plant and leaf count of the plant. The length of the plant will be measured using a ruler. With the plant on the side of the clear cup it will be easy to distinguish the length/height of the plant, by simply placing a ruler against the cup and straightening the plant so that it can be in line. The leaf count will also be recorded within the results. Leaf count will be performed by counting every leaf visible on the plant. With both the leaf count and the height of the plant known it will be recorded and shown with in two types of graphs. The first will be a table. The table will show the results of both the things recorded. Those same results will be shown within a line graph. The line graph will show the results of the plant every time it is recorded. All results will be calculated to the average when shown or placed in graphs.

To ensure that my results are reliable I will perform this experiment using three plants to each light to ensure that if one goes wrong I’ll still have two others to look upon. As a result I will be able to tell whether something has happened to the plant that doesn’t consist of the lights involvement.

The way I would analyse my results is by calculating the average of the results for each coloured light. Then I would place them together wether in a table, line graph or both then see if there is any significant difference between the results of each light. I would also compare each result to one another and see what has happened to this one in comparison to another one. I would make not of the difference each of them have that others didn’t. I would make and observation on which one has grown best in terms of height of the plant. I would make reference in my results of what happened to the plants and make an overall statement about whether my theory/ hyposest was proven right or wrong.

A professional that I could contact for additional scientific information or help for my project could be Miss Blevin who is an expert in science for year 9, Mr Jeffersin who is incredibly intelligent with knowledge all about science and happens for us to be privileged with having him work as a causal and replacement teacher at our school, Mrs Park who taught me in science for two terms, Mrs Woods who is said to be extremely smart and also teaches at Freeman, Ellis Bou-harb who studies at Sydney University and is currently doing a _____ ______ ______ _____. I will be able to contact any of the above when needing additional scientific information or help for my project.