Potassium Effects on Aeroponic Plant Growth

Katie Evans10th Grade

Berwick Area High School

Research: Aeroponics- a technique for growing plants without soil or hydroponic media. The plants are held above a system that constantly mists the roots with nutrient-laden water

Roots are suspended in an air environment NO soil is used Rockwool- a fibrous material used as a growing medium. This is used in aeroponic systems

This method of growing is proven to have a less risk of plants becoming ill or getting diseases

Plants need at least 16 different nutrients to survive.

All nutrients are present in a nutrient solution which is a mineral rich solution given to plants.

Research(Continued):

Giving plants too much of a nutrient can be just as detrimental to the plant as not enough

Potassium is required in plants to ensure protein synthesis and the opening and closing of the stomata. It also plays roles in photosynthesis and the activation of enzymes.

Potassium deficiency can occur If potassium deficiency occurs the leaves on the plants will look scorched.

The leaf tips can also curl or the yellowing between veins can occur

Research(Continued): • This nutrient

solution is the base solution I used for all trials

• This bottles Ratio is 2-1-6 meaning there is 2% nitrogen along with 1% phosphate. As well as 6% soluble potash

• This is potash fertilizer and is the potassium I added to the base solution for the experimental trials.

• This bags ratio is 0-0-6 meaning there is 0% nitrogen along with 0% phosphate. As well as 60% soluble potash

Question:

Will added potassium help or hinder the growth of

plants ?

Hypothesis:

If I add extra potassium to a nutrient solution and grow plants aeroponically and a trial of plants with just nutrient solution then the plants grown with the added potassium will grow tallest and weigh most. Because potassium is essential for plant growth and 12% rather than 6%would be beneficial for the plant.

Variables:

Independent variable: the amount of potassiumDependent variable: height in centimeters and dry biomassControl: the plants grown with just regular nutrient solutionConstants: light, water, receiving nutrients through solution, location

Materials: 1 rubber maid tub 12 net pots 4 water sprayers 1 water pump 1 timer 3 heat lamps 3 light bulbs(25 watt)

Pea seeds Nutrient solution Silicone Distilled water(in gallons)

Clay pebbles Rockwool Black hose

PVC pipe PVC T fitting 2 PVC endcaps PVC cement Graduated cylinder Measuring instrument with centimeters

Funnel Potash Data collection charts

Before the experiment begins (building the aeroponic system):

1. Obtain all needed materials2. Take the lid off of the tub and arrange the locations and

placements of the net pots3. After the net pots are placed use a writing utensil to race

around the circumference of the net pot on the lid4. Then cut out each circle and discard of the unneeded material5. Then file out all the rough edges to ensure the net pot fits6. Then take the tub and looking down in it measure 4 inches down

on each side from the top7. At those two points drill/cut out a 1 inch sized hole. Ensuring

the PVC pipe fits.8. Then take two 16 ½ inch PVC and attach them together using a

PVC T fitting9. After that slide the whole thing into the two holes already

drilled in the sides10.Then place a fitting that is for the water pump into the

bottom of the PVC T fitting

Before the experiment (building the system)(continued):11.After that place the water pup in the bottom of the tub

directly under the PVC T fitting12.To attach those two take a black hose and place it into

the water pump fitting and run it down to the water pump

13.Then going back to the two 16 ½ inch PVC pipes with the T fitting. On the top of these pipes drill 4 equally spaced holes for the sprayer stems to fit in and are secure

14.After that go to the outside of the tub and place a PVC endcap on each of the pipes sticking out

15.Secure with PVC cement16.Seal around the pipes inside of the tub with silicone17.Plug up any unneeded holes with silicone18.Wait until dry19.After it dry's clean out an debris or material20.Plug in the system21.Run plain water through the system several times

You must germinate the seeds before you start the Experiment:

1.Obtain a bowl2. place a half inch of water in the bowl3.Take the seeds and dump them onto a paper towel

4.Crumple up the paper towel around the seeds

5.Place the paper towel and seeds into the bowl of water

6. leave them there until they begin to sprout ( 1 or 2 days)

7. then you may continue the experiment

How to begin the experiment and how to maintain it :1. Place the aeroponic tub in an adequate space2. Place heat lamps above the tub3. Place a lightbulb in each lamp4. Plug in all the lamps5. Attach a timer to the lights6. Place distilled water in and pour it in the tub until the

water intake slits on the pump are covered7. Determine how many gallons of water there are in the tub8. After determining that place 2 teaspoons (10 mL) of

nutrient solution in the tub for each gallon for water9. Take the Rockwool and soak it in water10. make slits in the Rockwool and place the germinated seeds

in 11. set the Rockwool and seeds into the net pots12. fill the remaining space with clay pebbles13. place the net pots into their circular holes14. plug in the system15. leave the system running for 24 hours a day with the

lights running for 16 hours 16. For the trial that involves potash place in 13.255 for

every 221 ml of nutrient

How to mix the Experimental solution:

• In a quart bottle of nutrient solution there are 221ml of nutrient solution

• 1 teaspoon is equal to 4.92892 ml• 1 teaspoon equals .00520833 quarts • The amount in quarts left in the bottle of nutrient solution equaled .2335280203 quarts

221 mL

4.92892 mL

1 teaspoon

1 teaspoon

.00520833 Qt= .2335280203 Qt.

• If there are 56.76 grams of potash in a full quart bottle then how much is left in .2335280203 quarts ?

56.76 grams

1 Quart =

X

.2335280203 quarts

X= 13.255 grams

That is how much potash is left in the bottle. To achieve 12% I must add 13.255 grams to this

Actual Setup:

Trial Size and Number:

2 trails 12 plants in each trial

24 plants in total

2 trials 12 plants in each trial

24 plants in total

Nutrient solution: Nutrient solution and Potash:

Data Recording:

To finish my experiment I will measure, analyze , and collect my data

Every 2 days for a total trial length of 8 days the plants were measured in centimeters and recorded on a chart like this. They will be compared to other trials

At the end of each trial the plants were measured by dry biomass and recorded and compared to the other trials

Calculating Dry biomass:

Trial Result photos: Trial 1 Control solution (Day 8):

Trial 2 Control solution(Day 8):

Trial 1 Experimental solution (Day 8):

Trial 2 Experimental solution (Day 4):

Trial Result photos: Trial 1 Control solution (Day 8):

Trial 2 Control solution (Day 8) :

Trial 1 Experimental solution (Day 8):

Trial 2 Experimental solution (Day 4):

N/A

Results: Control solution trial 1 Day 0

Height(cm)

2Height(cm)

4Height(cm)

6Height(cm)

8Height(cm)

Dry biomass(g)

Plant 1 0.00 0.00 0.40 3.50 4.10 0.133

Plant 2 0.00 0.00 0.00 1.10 3.90 0.232

Plant 3 0.00 0.00 1.10 3.60 7.10 0.172

Plant 4 0.00 0.40 2.00 4.10 6.80 0.229

Plant 5 0.00 0.00 0.00 0.00 1.10 0.205

Plant 6 0.00 0.20 2.10 4.60 8.00 0.231

Plant 7 0.00 0.00 1.00 2.20 4.10 0.238

Plant 8 0.00 0.00 0.80 3.80 6.40 0.183

Plant 9 0.00 0.60 1.90 4.60 7.20 0.184

Plant 10

0.00 0.50 1.60 4.40 7.20 0.164

Plant 11

0.00 0.00 0.60 3.90 5.70 0.183

Plant 12

0.00 0.40 1.30 4.40 8.50 0.278

Results: Control solution trial 2 Day Day 0

Height(cm)

2Height(cm)

4Height(cm)

6Height(cm)

8Height(cm)

Dry biomass

(g)

Plant 1 0.00 0.00 1.10 3.10 6.00 0.278

Plant 2 0.00 0.00 1.70 3.90 6.80 0.198

Plant 3 0.00 0.00 2.10 4.40 6.30 0.214

Plant 4 0.00 0.00 0.30 2.30 4.60 0.254

Plant 5 0.00 0.00 2.40 5.90 9.20 0.215

Plant 6 0.00 0.00 0.00 1.60 4.70 0.291

Plant 7 0.00 0.00 0.00 0.20 4.50 0.286

Plant 8 0.00 0.00 0.30 2.20 3.70 0.293

Plant 9 0.00 0.00 1.90 4.20 6.40 0.172

Plant 10

0.00 0.20 2.70 5.50 7.90 0.236

Plant 11

0.00 0.00 1.50 3.30 6.40 0.235

Plant 12

0.00 0.00 2.00 4.20 7.20 0.247

Results: Control solution averages

Day Day 0Height (cm)

Day 2Height(Cm)

Day 4 Height(cm)

Day 6Height(cm)

Day 8Height(cm)

Dry biomass (g)

Average

0.00 0.10 1.20 3.38 5.99 0.223

Standard

Deviation 0.00 0.19 0.85 1.53 1.85 0.044

Standard Error 0.00 0.04 0.17 0.31 0.38 0.009

Results: Experimental solution trial 1

Day 0Height(cm)

2Height(cm)

4Height(cm)

6Height(cm)

8Height(cm)

Dry biomass(g)

Plant 1 0.00 0.00 0.00 0.00 0.00 0.282

Plant 2 0.00 0.00 1.20 3.10 5.90 0.228

Plant 3 0.00 0.00 1.60 3.50 5.30 0.173

Plant 4 0.00 0.00 0.00 0.00 0.00 0.233

Plant 5 0.00 0.00 0.00 0.00 0.00 0.00

Plant 6 0.00 0.00 0.00 0.50 1.90 0.156

Plant 7 0.00 0.00 1.90 5.20 7.60 0.223

Plant 8 0.00 0.00 0.00 0.00 0.00 0.00

Plant 9 0.00 0.00 0.00 0.00 2.00 0.186

Plant 10

0.00 0.00 1.30 2.30 4.40 0.241

Plant 11

0.00 0.00 0.00 0.00 0.00 0.143

Plant 12

0.00 0.00 1.10 3.30 6.10 0.178

Results: Experimental solution trial 2

Day 0Height(cm)

2Height(cm)

4Height(cm)

6Height(cm)

8Height(cm)

Dry biomass(g)

Plant 1 0.00 0.00 0.00 N/A

Plant 2 0.00 0.00 0.00 N/A

Plant 3 0.00 0.00 1.30 N/A

Plant 4 0.00 0.00 0.00 N/A

Plant 5 0.00 0.00 0.00 N/A

Plant 6 0.00 0.00 0.00 N/A

Plant 7 0.00 0.00 0.00 N/A

Plant 8 0.00 0.00 0.00 N/A

Plant 9 0.00 0.00 1.60 N/A

Plant 10

0.00 0.00 0.00 N/A

Plant 11

0.00 0.00 0.00 N/A

Plant 12

0.00 0.00 0.20 N/A

Results: Experimental Solution Averages

Day Day 0Height (cm)

Day 2Height(Cm)

Day 4 Height(cm)

Day 6Height(cm)

Day 8Height(cm)

Dry biomass (g)

Average

0.00 0.00 0.59 1.49 2.77 0.170

Standard

Deviation 0.00 0.00 0.76 1.87 2.91 0.089

Standard Error 0.00 0.00 0.22 0.54 0.84 0.026

* Averages reflecting one trial with 12 plants

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

Average Plant Height (cm)

Time (days)

The effect of varying concentrations of potassium on average plant height in

pea plants

ControlSolution

ExperimentalSolution

0 2 4 6 8

0.000

0.050

0.100

0.150

0.200

0.250

Dry biomass (g)

The effect of varying concentrations of potassium on average dry biomass in pea

plants

ControlSolution

ExperimentalSolution

Unexpected Outcomes: • Seeds began to rot and disintegrate in the experimental trials

• Pink foaming mold began to grow on the seed of plant 5 in the Experimental solution

Sources of Error:

The plants were placed in the Rockwool upside down. Therefore the roots had to grow up and then back down to receive water Slightly inaccurate measurements of nutrient solution On the last trial of the experimental solution a lightbulb had gone out

Improvements and Further experiments:

• Although the system was fixed a leak was a persistent problem

• Have a larger trial size• Have a longer growing period• Allot ample time for the last trial

• If I were to do a following experiment I would make sure all these factors were fixed

Conclusion:

The purpose of this experiment was to test varying concentrations of potassium on aeroponically grown pea plants. In this experiment, the concentrations were 6% and 12% potassium. The major findings in this experiment were that there was statistical significance in the data suggesting that the plants grown in the control solution grew taller and had more dry biomass. The hypothesis stated that doubling the concentration of potassium(12% rather than 6%) to a nutrient solution used to grow plants aeroponically would result in taller plants with more biomass. To improve this experiment I would have a longer growing period with more trials.

References:Aeroponics. (2014). Retrieved November 16, 2014, from The Free Dictionary website: http://

www.thefeedictionary.com/aeroponics.ESSENTIAL NUTRIENTS. (2015). American Nurseryman, 16

Hemmerly, T.E.(2015). Nutrient Requirements in Plants. Salem press Encyclopedia of Science, Retrieved from: http://eds.b.ebscohost.com/eds/detail?sid=5804e9a3-e2a3-4b24-849f

14fcda2e26c3%40sessionmgr/20&vid=10&hid=112&bdata=JnNpdGU9ZWRzLWxpdmU%3d#AN=89551777&db=ers

How Aeroponics Work. (1998-2014). Retrieved November 14, 2014 from HowStuffWorks website: http:// home.howstuffworks.com/lawn-garden/professional- landscaping/alternative-methods/aeroponics5.htm

How Does Aeroponics Work? (2012). Retrieved November 16, 2014, from Rocketswaf.com website:http://ww.rocktswag.com/gardening/hydroponics/aeroponics/how-does-aeroponics-work.html

How Does Aeroponics Work. (n.d.). Retrieved November 16, 2014, from Best Hydroponics 101website: http://www.besthydroponics101.com/howdoes-aeroponics-work

Nutrient used In Hydroponics. (1997-2010). Retrieved November 18, 2014, from Garden Guides website: http//www.gardenguides.com/123372-nutrients-used-hydroponics.html

Potash. Retrieved January 9, 2016 from.http://en.wikipedia.org/wiki/potash

Potassium in plants. Retrieved from. wwwsmart-fertilizer.com/articles/potassium-in-plants.

Templates, sora. Potassium (K) and its importance in plants. Retrievedfrom.http://agricuturalinformation4u.blogspot.com/2015/03/potassium-k-and-its-importance-in plants.html

Thank you. Do you have any questions ?

By: Katie Evans