Does coffee affect plant growth?

by Hashem Hijjawi

Does coffee affect plant growth? Does it kill the plant? Or make it grow at a faster rate. What effect does it have?


Yes, coffee grinds can certainly effect plant growth.

Far from killing your plants, the coffee will stimulate growth.

Coffee grinds are high in nitrogen, an element essential to plant growth and a major ingredient in commercial fertilizer.

You can either sprinkle the coffee grinds directly onto the soil, or add them to your compost bin or pile.

If you add them directly to the soil, keep in mind that coffee is also acidic, so you may also want to add something alkaline, like brown leaves.

I hope this information helps.


Comments for Does coffee affect plant growth?

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Jan 18, 2022
by: brasanha (brazil and spain

We came from so far away curious about this. And with your help, WE MADE IT!!!
Now we know that everything is possible in this site, and that our grade in class won't be 0! We will share this with our culture and make sure everyone is aware of the affect of caffeine in the growth of plants. thxx see ya✌🏼 peace out

Oct 04, 2021
by: Anonymous

It is very cool

Jan 26, 2021
by: Silver 3

thanks for the info i have a science project on this and appreciate the help :)

Nov 18, 2020
by: Deadly chicken nuggets

Yay so cool

Aug 30, 2020
by: Bear Grills

This REALLY helped me in my adventures! Thanks!

Oct 07, 2019
Thx queen
by: Ariana Grande

This was so helpful like this is SO AMAZING!!!! I am literally thinking of making a song about this this amazing site! THXXX

Sep 20, 2019
by: Rose

What is the published date/publisher.

P.S whats the website title too?


Feb 11, 2019
so much help
by: Anonymous

keep this site up. this was so much help for my research for my science fair soon. thanks so much...such a help. i wish there was some more details and info about it but it is oki.

Mar 24, 2018
by: Anonymous

Thx so much. Im in 5th grade and its pretty hard finding at least 7 sites 4 my project. you r the best #thx #saviour

Feb 04, 2018
need info
by: Bob Mlarky

Can you add more info

Jan 21, 2018
by: Anonymous

how much do they differ. Im doing my project with bean plants and they arent growing fast enough!!! its due tomorrow!!

Jan 09, 2018
by: Anonymous

thank you so much for this idea!!!!! I also used this website for my report and it helped a lot thanks!!!!!! :) :)

Dec 14, 2017
by: babyfawn

thx this helped A LOT with my project

Oct 28, 2017
by: Anonymous

thank you so much. I have my problem statement and my hypothesis due on tuesday and I need to do them today, This really helped

Oct 23, 2017
by: JUJU

Thanks so much for this info it really helpful because I am doing a science fair projects and this was really good information

Sep 20, 2017
Plants and Coffee
by: Donutttttttsssss

Thanks so much!!!! This really helped me because I'm doing a science fair and I was going to add the coffee right in until you mentioned the brown leaves!! Thanks again!!!XD

Mar 15, 2017
Thank Bruh
by: Anonymous

Thanks a lot Nick this helped me with my science project sooooo much #udabest#awesome

Nov 27, 2016
Thank You(:
by: Chloe

This helped me so much on my science experiment (:

Jul 30, 2016
coffee makes excellent plant food
by: Anonymous

I don't use the coffee grounds because that makes a mess. They mold in the planter dirt. I pour my left over brewed coffee on my houseplants & they start growing much bigger, and healthier & fast! So, the secret appears to be nitrogen in coffee. I've wondered what is in the coffee that stimulates plant growth, so much better than plant food you buy.

Apr 13, 2016
by: abby

Im eleven and did this at Macon county r-4 school and it got me an A

Mar 21, 2016
by: Katy perry

this helped alot because im learning about dicot and monocot plants and i have to do something for the science fair and this absolutley helped me

Mar 12, 2016
not always true
by: Anonymous

certain plants are positively effected by adding the coffee grounds to the soil...but others, such as sunflower seeds, are negatively effected. Coffee grounds inhibit the growth of sunflowers.They grow slower and are not as big and healthy looking.

Mar 03, 2016
by: Abigail

Thanks that really helped

Mar 03, 2016
Thanks by Abigail
by: Abigail

Thanks for the help it helped alot im in 4rth grade and my project is on this thank you so much

Feb 09, 2016
by: Anonymous

Thanks for the research

Feb 04, 2016
by: michael

thank you so much!!!!!!!!

Feb 04, 2016
by: mike

helped a lot thanks

Sep 30, 2015
by: Anonymous

So i am in the 11th grade and me and my partner are doing this as our project... will snapdragon flowers work for this... i have my doubts but i dont know... i want to try a simpler plant but my partner doesnt... any suggestions?

(sorry for any miss spelling)

Apr 01, 2015
What Plant should I grow?
by: Anonymous

What plant should I grow that will grow fast and somewhat tall and will show reactions to the coffee?

Mar 04, 2015
by: Anonymous

this goes aginst my research i dont know if this only happend to me or if i did something wrong

Jan 23, 2015
by: Anonymous meowser

i have to do a science fair project and i chose if coffee or water is better for a plant. this site helped a lot and i recommend using this site if u need to do a project. thx for the help :)

Jan 07, 2015
by: Anonymous

It actually works! I did a science project where you water plants with different liquids and coffee grew 10.5 centimeters in a week! This was great info for my research paper for the project. Thanks!

Dec 21, 2014
oh damn.
by: Millie

So I did this for my science project and it killed my plants tf. Ms.TH=ompson bout to kill meh now doe lmao

Dec 14, 2014
by: Anonymous

I did this for my science fair project and the plants didn't grow well. Does this have anything to do with that the coffee used was 5 years old?

Nov 09, 2014
Science project
by: Anonymous

Im doing a science project to see if pouring coffee on plants help,it grow taller.From all your comments I hope it works because I would hate to kill a plant

Nov 07, 2014
How will coffee affect the growth of beans in comparison to soil?
by: Anonymous

I am a teacher and I have done this project with my students for two years now. I have actually grown four seeds per pot in coffee grinds in three different pots, and four seed in regular soil in three different pots. The results have been fabulous the seeds grown in coffee grinds have grown faster and healthier, than the ones in regular soil. For the record the ones grown in coffee grinds germinated faster and the leaves were wider than the ones grown in soil.

Editor's Note: Great feedback. Thanks!

Sep 27, 2014
by: Anonymous

I don't think this is true

Mar 09, 2014
it dont work
by: Anonymous

i didn't know it was supposed to help them by my oservering it actually killed or seriously "injuring them"

Nov 07, 2013
by: Anonymous

hey im in fith grade and im wondering if hot liquid coffee makes a bean plant grow faster than hot cofee

Dec 18, 2012
by: Anonymous

im doing this for my science fair project, should i use warm coffee or hot

Sep 12, 2012
soft drinks
by: Anonymous

Can you give a plant caffeinated soft drinks? Would the carbonation kill the plant?

Editor's Note: Not sure that's a good idea! Never mind the carbonation, think about all the sugar!

Aug 05, 2012
7th grade project
by: Duchesse

im thinking of doing this for my 7th grade science project too. But instead of coffee grinds im using coffe in the liquid. hope that will work to.:

May 02, 2012
My experiment...
by: gr.5ScienceStudent

I use a K-cup coffee machine, and I water my plant 3 tbs every day with the second run of liquid coffee. I've been doing this for 34 days and so far, my plant is 28 cm tall, and has enormous leaves. Did you try sprouting the seed? oh, and I used bean plants. Anyways, put the seed in moist paper towel, put that in a closed ziploc bag, put in sunlight for about 3 days, and when you check on it the root should've started to grow(that is how youy sprout a seed) Then plant it and start giving it coffee! I'm doing this for my grade 5 science fair, and this is actually a good topic!! We had to do an experiment, and this is mine!

Apr 30, 2012
by: nana

i hope this works:)

Apr 08, 2012
by: A Mad Student.

I did my entire science project on this thing. Decided to actually trust tis website, you know, and use the info to do my Science Fair Project for 2012. Did my hypothesis, spent my dollars buying Coffee and plants and soil. Planted th plants and sat back, waited for the plants to grow. After 3 weeks, no growth and I began to worry. I saw one plant start growing and that was all the growth; it died shortly after. Maybe the effects of coffee vary depending on plant, or whatever, but I failed; not a happy camper here.

Apr 03, 2012
by: Anonymous

so i am doing this for my science experiment and i really hope it works....

Feb 07, 2012
by: Anonymous

I'm in Junior high but i am doing it for science fair it is really it is hard but worth it well hope you try it sometime .

Feb 04, 2012
by: Anonymous


i am so doin this project workin soo hard on it good luck to all others who do it to
ttyl :)

Nov 21, 2011
by: Takerevenge

Okay, now I know what to do my project on and what to have in the morning.

Nov 09, 2011
by: Anonymous

this is rare and an unusual combination for plants this surprised me and my project is gonna rock the judges minds!

Oct 12, 2011
Science Fair Project
by: Anonymous

I am entering our 7th grade science fair and working on which fertilizer works best. Coffee is one of my fertilizers. I hope that this works. By the way, people that said it didn't work, you're supposed to soak used coffee grounds in water then use that mixture.

Oct 04, 2011
by: Yo mamma

This project was awsome. everyone should do it. I got an A +

Sep 08, 2011
science fair
by: skittles

hope this works

May 23, 2011
by: No Amber

sort of works but mine died after 4 days it died

Feb 20, 2011
it didn't work
by: Anonymous

thanks for the idea. but it didn't work and i got a B-

Feb 18, 2011
Didnt work :'(
by: Mr Male Man

the coffee mixture stopped my plantfrom growing. the coffee made the soil so sticky that the water and nutrients can't go in the roots.

Feb 17, 2011
hope it works
by: Anonymous

I'm entering it in my school science fair. don't fail me now.

Feb 14, 2011
by: Anonymous

by: Anonymous

this really helped with my science fair project cuz i gota do a 1age research paper but it helped alot

Me too.

Feb 10, 2011
by: Anonymous

hope this works 4 science fair

Feb 07, 2011
science fair help
by: Anonymous

this website help me a lot on my science fair.
but i need too know when this website was made.
pleasee tell me!!!

Editor's note: Started in 2005, and ongoing.

Feb 06, 2011
science fair
by: Anonymous

Hope your right! I am going to enter the science fair seeing if coffee grounds or fertilizer works better on plants!

Jan 28, 2011
science fair
by: Anonymous

thanks this helped my science fair research. i'm gonna see if coffee, pepsi, or water helps the best in the growth of plants.


Jan 21, 2011
coffee grinds and left over coffee
by: Anonymous

Yes..the liquid does work on the growth of the plants. I did this a long time ago with a house plant and it grew so big. The vines even grew so long i had to use thumb tacks and a string to hold them up along the walls of the house.

Now, I am helping my son do his science project on this with watermelon seeds. One is with coffee grinds mix with soil, another one with the soil left over from our garden last spring (mix with 19/19/19 and lime, and the other one is by using a starter pot. We are going to see which one will sprout first.

Jan 11, 2011
by: Anonymous

well i'm doing an experiment on the effect of caffeine and coffee grinds on radish and garden bean seeds... just started today, actually. lol
thing is, i did an experiment in 4th grade and i watered one bean plant with milk, one with water, one with apple juice, and one with diet coke. The one with diet coke grew the most efficiently. The one with milk and apple juice stunk, but the milk one died. The one with water grew like a normal plant would.

Jan 10, 2011
by: Anonymous

i cant believe this many people are doing the science fair project on the same thing -_- i was gonna do it but after reading these comments i changed my mind

Jan 02, 2011
by: Anonymous

this really helped with my science fair project cuz i gota do a 1age research paper but it helped alot

Dec 15, 2010
by: Adam D'Andrea

yo, thx alot brother..this really helped me with my science fair project

Dec 10, 2010
Helped me sooo much
by: Anonymous

thank you! you helped with me science fair project! your a life saver!!!!

Dec 06, 2010
by: Lizzy Johnston

thanks for this article it really helped with my school science project and with gardening! =]

Dec 05, 2010
by: amanda

thank you this is so interesting and it helps with my science project!!!! ;-)

Nov 30, 2010
by: Anonymous

thanks for the info but how does coffee work when it is liquified?

Nov 23, 2010
by: ----ANOM-----

thanks! it really helped....but I need to know about the LIQUID!! please! thanks thou!!!

Nov 21, 2010
by: ven anito

thanks bro u help me big time

Nov 21, 2010
by: Anonymous

thx soooooooooooooooooooo much this helped me a lot and im almost done with the project thank u sooo much :)

Nov 21, 2010
thank ya
by: S-M-H

thank you soo much now i know the answer!!! <3

Nov 18, 2010
by: Anonymous

thats all i need for my research thanks

Oct 30, 2010
by: Anonymous


Oct 14, 2010
caff and decaff cofee
by: kal ra

do caffeinated coffee and coffee without caffeine give the same results?

Oct 13, 2010
This helps so much but......
by: Eefie Bunk

This really helps but it would help more if you figured out how LIQUID coffee works the same way. This would help me so much for a science fair project! But please figure out if liquid coffee works better ! thanks
- Love Always
Eefie Bunk *<:]

Oct 06, 2010
by: Anonymous

I would like to know about LIQUID coffee's effect

Oct 06, 2010
im so relived
by: thx ppl

im doing this 4 a sceince project and u ppl help my so much il black 2 l0l

Oct 03, 2010
soo confused
by: gahh!

lol im doin this right now and i have to do 5 sources n my brain hurts from researching so much! D: i shouldve planned this out well... it was so easy in my head rofl... wish me luck! :D

Oct 01, 2010
by: science peeps a & s

thank you we are using this in out\r science fair project.

Sep 30, 2010
Helped me out!
by: Anonymous

Hey guys, this is an awesome article, and was sooo helpful! I noticed that a lot of people were doing projects on this, and so am I. There is a lot of information that you also need to know, so go to:
There are also a lot of other sites, such as:
Ooh! And:
Hope this helps you guys!

Sep 27, 2010
need help
by: chrissy pooh

yes im doing this for a project som one hellllllllllllllllppppp me lol

Sep 27, 2010
plant v.s. coffee
by: Chris O.

I am using this for my science fair project and I think it will really work. I really think this will help me in 9th grade.

Sep 19, 2010
by: koolgal

this website is the bomb i will know 2 com on here agian 4 another science project....:]

Sep 18, 2010
sciencefair facts
by: koolgal

i am doin this project this year and soo far i have my hypothisis my problem and variabls and still have a long way to goo. we wont be starting our projects till mid october OMG!....oh well head starts are better than nothin any advise people....i relly need iy thnxz sooo much;]

Sep 16, 2010
by: I_Need_Help

I'm doing the same project and I just want to ask what plant did you use? I wish it's a fast growing plant because we only have 6 months to do it.

Sep 11, 2010
Lots of questions..
by: StudentInDistress

*What type of plant did you use?
*What kind of soil should I use?
*What brand of coffee did you use?
*How did you add the coffee to the plant? Did you make coffee, then water the plant with it instead of water? Did you replace the soil with unused coffee grounds? With filtered coffee grounds? Or did you sprinkle the soil with unused coffee grounds? With filtered coffee grounds?
I am very confused with how to perform this experiment. I want to make sure that I have doen this right in every possible way.
I would also very much appreciate it if you would tell me the step-by-step procedure you used while performing this experiment. The materials and equipment you used would also be very helpful.
Thank you so much for your help!

Jul 03, 2010
by: Anonymous

dont add too much, i put about a gallon of used coffee grounds in my rose bushes bed each week... few months now and its dead..

May 18, 2010
so watts the conclusion??
by: Anonymous

i too am doing the same project. I have been using diluted coffee powder for one plant and plain water for the far the one with plain water seems to be taller by a few inches.....shouldnt the plant with coffee water be taller??? plz reply!!

May 14, 2010
thank you
by: david

i am doing a science project on this and this really helped me

May 13, 2010
by: Anonymous

I got the opposie!

May 12, 2010
by: Anonymous

can you tell me about brewed coffee and its effect on plants?

May 12, 2010
by: Anonymous

Lier! No sike you are right! I made a science fair on this topic and you are absolutely right!

Apr 28, 2010
by: Anonymous

this will realy help me with my science fair project its like three fourths of my grade

Apr 28, 2010
My Project
by: Jhakari Sarvis

This really helps me because I'm doing a Science Project for our school science fair so if u dont know about this site i really really REALLY recommend it to you.

From Jhakari Sarvis aka Yung Ridge Park numba 12

Apr 23, 2010
by: Anonymous

Wow this looks like a project I should do!!! =D =D =D =D

Apr 21, 2010
by: Anonymous

My teacher made me stay 'til 6 p.m. until I came up with an idea. My mom is furious thanks

Apr 20, 2010
by: kylaaa :)

i seriously lost all hope till i found this forced to do a science fair project on this and it really helps alot....thank you!

Apr 19, 2010
Decafinated coffee
by: Anonymous

I had asked if decaffeinated coffee worked as well for plants as coffee with caffein. Thanks for any information that you can give me.

Apr 18, 2010
Thank U!!
by: Anonymous

im doin a science project on this too thanks soooo much for the help!!!

Apr 18, 2010
Coffee grounds for plants
by: Anonymous

Does decaf coffee work as well for plants as caffinated? I just learned of this and am eager to try it but I drink mostly decaf.

Apr 13, 2010
by: Cindy

OMG LIKE THANKS LIKE SO MUCH THIS LIKE HELPED ALOT!im like doing this for like my science fair project and like this info is like so good.

Mar 29, 2010
by: Jacky Yu SBSH


Feb 28, 2010
by: Gurl123

I am doing this for my project and I was so confused but when I found this website I was finaly Calm thx for the website :)

Feb 26, 2010
me too
by: woohoo

im using this for my science fair project too,
OMG! this is crazyyy guys!

Feb 01, 2010
help Im doing a project
by: Anonymous

how does it help the plant grow faster with a brown leaf

Jan 25, 2010
by: Science

I used it with exotic angel plants for my project and the one with coffee sprouted way better

Jan 22, 2010
by: Anonymous

omg i'm doing that for my science project too!

Jan 20, 2010
Trying something else
by: Ron

I tried something else i tried putting the seeds in an area of coffee grinds but surrounded the grounds with regular soil.(Variable) (Hypothesis) I thought after reading all the online articles it would grow a lot!!! (Conclusion) After about 2 weeks i started to take data and figured out that my idea was not so succesful. (Control) Put the same plant in regular soil or a group you can come up with.

If you can plz try this and see what results you get i'd like to see if i did something wrong or if i was just doing this at the wrong time.
Thank You

Jan 15, 2010
by: Anonymous


Jan 15, 2010
Coffee grounds or black coffee itself??
by: Anonymous

What kind of black coffee was used? Was it used cold or warm? My son has a science project due in March, and we need all the help we can get!!

Jan 10, 2010
Science Fair
by: kelly

the coffee really grew way better than the water.I am soooo happy!:}

Dec 02, 2009
It worked better than water
by: Dad

My daughter did this experiment with petunias. The black, straight coffee grew the plants as good as or better than the water. Milk...not so good...they died.

Dec 01, 2009
by: Anonymous

I did a science fair project and i used coffee as one of my liquids to water plants. It grew really tall! But not as tall as the water (control). :(

Nov 29, 2009
by: Anonymous

omg thats my science fair project 2. my plants died

Nov 26, 2009
by: nat <3

thank u this information is goin to help me out a lot now eith the project im workin on

Nov 18, 2009
by: 8th grade student...

Hey im using bluegrass plants, and it is working very well! I am using different household compounds to grow them. So far plane water is growing te best!! thanks for the help!!

8th grade student...

Nov 17, 2009
by: Anonymous

thnx lots of help with project

Nov 05, 2009
by: Anonymous

thanx 4 all the help i really needed it kuz my science fair project is does caffeine effect plant growth and i am using coke, coffe, tea.thanx 4 da help nick

Oct 31, 2009
Diluted coffee
by: Anonymous

This article is about coffee grounds JUST as fertiliser, NOT as a primary source of nutrients. If you water your plant ONLY with undiluted coffee it will almost certainly die. For your plant to survive you must dilute the coffee, and ideally continue watering your plant with water, using the coffee only as a fertilizer.

Hope this helps anyone who is doing an assignment!

Oct 28, 2009
why hello there
by: PoptartAndSkittlez

im gonna use this for my project becuz i want too. gotta problem punk? i didnt think so. lol smiley face

Oct 21, 2009
by: Anonymous

I have a question... I am doing "Does Caffeine Affect Plant Growth?" is your info onlly for coffee grinds or can it be for just plain coffee ? what kind of fertlizer should i use ?? THANKS 4 THE INFO !!!!!!

Oct 20, 2009
by: Brittany

haha this is my science project too :)

Oct 07, 2009
by: hi

this was my science project but the coffee killed my plant =( it never grew. do i have to add water to the coffee??

Oct 05, 2009
by: hi peoples

my project tooo thx this helped a lot

Oct 04, 2009
Science Project
by: Anonymous

haha that's so funny that's my science project to! I didn't know that many people would actually think of t but then again there are SO many people in this world! haha

Sep 26, 2009
by: Anonymous

thnx...i really help me with my science prjt!!!! :D!!!

Sep 26, 2009
by: Anonymous

Thanks for all of the information! I am definatly going to use this for my science project.

Sep 23, 2009
by: Anonymous

thank you i needed this for my project

sincerly hule kua students 5 grade A2

Sep 18, 2009
thank u
by: Anonymous


Aug 23, 2009
Cuban coffee grounds
by: Leroy_Brandon

Word = cardna

I brew Cuban coffee expesso every morning in my Mr. Coffee. Six scoops per 6 cups of water.

I place coffee grounds with the filter at the base of each plant. Growth is healthy and vivrant. Colors are dark and rich.

I though it was an old wife's tale but it really works.

May 27, 2009
@ Emily
by: Anonymous

I just thought that you should know that the article only speaks about coffee grinds. When you use the actual coffee the acidity increases and you lose some of the nutrients... I did the same science project and I did not know this information beforehand and our plants died...

May 25, 2009
I disagree...
by: Emily A

me and my friend did this same question for our science project, but instead of using coffee beans we used the coffee itself. We found that it actually stunted the growth of the plant bu a few centimetres (we used a radish plant...i dont know if that makes a difference :S)

Apr 29, 2009
by: Gumec

how can we decrease the acidity?
what can we add to coffee(something harmless)in order to regulate the pH.

Editor: Crushed egg shell. Seriously. Quite common in Northern Europe.

Apr 16, 2009
by: roodnie

thanks now i can do my science project on do tea or coffee affect a plant thx again

Mar 25, 2009
by: Anonymous


Mar 19, 2009
thank you
by: jackie

thank you sooo much im doing this for my science fair project!

Mar 15, 2009
Far too Acidic.
by: Anonymous

I don't think coffee should be used in order to heighten plant health.

Feb 23, 2009
by: Anonymous

thank you iam going to use this for my science fair project

Jan 30, 2009
by: ruby

thank you so helped me to have an idea for my term paper......

Jan 12, 2009
by: Anonymous

this is perfect, you sure did amswer my question perfectly!

Jan 07, 2009
by: Shell

Wow thanks this really helps out alout. I can use this sometimes. Keep this site up.

Dec 01, 2008
by: Anonymous

i thought that was excellen info thanks a bunch!!!!!!!!!!!!!!!!

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