Do you touch your greenhouse plants?

Thigmomorphogenesis.

I love that word. :D It refers to a plant's response to mechanical perturbation (MP). This perturbation could be in the form of wind or rain, or inside a GH by air movement, brushing, shaking, or vibrating. An HAF fan is the origin of thigmomorphogenesis in many greenhouses.

Researchers have shown the benefits of mechanical perturbation to include height regulation, improved strength, and insect resistance. MP has been shown to upregulate genes associated with disease resistance.

My plants need all the disease resistance they can get. So in addition to using HAF fans (running 24/7), I have started touching or gently shaking the plants as I water or work in the GH. Does it work? Too early to know for sure, but it can't hurt.

Does anybody out there perturb their plants?

SB

Great thread, SB! I think this is right up there with talking to your plants. Some people think it's just plain dumb, but others believe that the act of talking to a plant gives it a "burst" of carbon dioxide, which can be beneficial. Of course, I resist the temptation to yell at the plants that aren't cooperating just in case "tone" can be detrimental! ;o)

I remember about a quarter century ago when there was a periodical called "House Plants & Porch Gardens" that I LOVED and read cover-to-cover every month... They had an article about the effects of surrounding elements on houseplants and they cited the long-since accepted effect of music (rock: bad, classical: good...) But another thing the article touched on was plants' reactions to us and other living things. It cited an example of a palm tree that a little dog (a JRT, I believe...) would sleep under. Well, the little dog became ill and was at the vet for a period of time. The palm inexplicably started to languish, but as soon as the little dog returned, the palm perked right up! I know some people will probably roll their eyes at this story, or call this pure coincidence, but I like to think that our interaction with our plants DOES have an effect.

Well, out to the GH I go to do some "plant stroking"...

Denise in Omaha

In 1970 a well known oral surgeon in New York, Dr. George Milstein created the mostly forgotton "Music to Grow Plants By." George was a big-time Bromeliad grower who really believed that it worked. I think there was some follow-up experimentation that suggested rock music actually was detremental to the plants.

I acquired George's Bromeliad collection after his death around 1976. He did manage to have a Bromeliad named after him, Aechmea milsteiniana. I haven't heard anything about the album for a long time.
Dave.

I remember reading about the experiment done where they somehow hooked up electrical wires ( I think thats how it was done) to get an "emotional" read on the plants' reactions to various actions done to them. One of the segments was where a man came into the room and started to butcher some of the plants and of course all the plants reacted negatively to it. Then the man left and the plants calmed done, and then he came back, and the plants just absolutely wigged out!! lol

One thing that I think people lose sight of, is that plants are living organisms, that have almost all of the needs that people do. Food, water, temp control for survival, reproduction etc. Why not emotional needs??? lol I am half joking here, simply because I haven't a clue how true the emotional needs are-I know that we humans tend to project our needs/thoughts on others,and that could be the case here. Given that, I will admit to doing a walk through the grhouses at night and checking out all the buddies...

I know SB started this thread on a whole other thought process-utilizing infomation in a technical form to grow better plants, but I think this twist it has taken is interesting.

There are lots of articles on using "touch" to regulate plant growth, I have never seen, though, that it would also toughen them up in regards to resisting pests/diseases. Interesting concept- I guess it comes under-"what doesn't kill you, makes you stronger"

tigerlily, that was Science Illustrated magazine that made that experiment. they even took out the mauled plant before the "purp" reentered the room and they still got a "negative" response from the other plants.
Everything we do- positive or negative DO affect all living things around us.
I dont rattle my plants but I do frecuently touch and stroke them as long as they dont have thorns and spikes :0))
Janett

I spend alot of time in the greenhouse. At this point I either have to admit that I talk to the plants OR I spend alot of time talking to myself ;-) Either way it makes us all happier!

Yes, it is an interesting twist the thread has taken.

Greengirl, the skeptic would say that the dog bumped the palm when he slept under it, providing some mechanical perturbation that benefitted the plant. Interesting.

My understanding of the research, based my reading on thigmomorphogenesis (I love to say it, not type it!), is that sound, whether it be music or voice, has not been associated with any effect on plants. There is some speculation that you could get close enough that you breath would move the plants, or that loud music would vibrate the plants enough to get a mechanical perturbation effect. In those cases it wouldn't be the sound per se, but the movement associated with the sound that caused the effect. I don't really know.

TL, here are just a couple of links illustrating the disease resistance induced by MP:
http://www.blackwell-synergy.com/doi/abs/10.1046/j.1439-0434.1999.147005313.x
http://www.amjbot.org/cgi/content/abstract/85/11/1586 Just a little more light reading...

Happy Growing (or brushing, stroking, perturbing or whatever)!

If you get a chance, check out "The Secret Life of Plants" by Peter Tompkins and Christopher Bird. Have been reading it off and on and it is really enlightening.

This is a nice summary: http://www.imok.ufl.edu/veghort/docs/height_121202b.pdf#search=%22thigmomorphogenesis%20wind%20bean%20disease%22

Brush your plants!

I always 'coon' my plants. That expression comes from the way a raccoon handles and washes everything. I am a touchy, feely plant thigmomorpho... pod

Well.. I am glad that someone else other than me had read that article about the plants reacting to the one being destroyed. I have been told I was nuts when I told that story. I wish I could find it somewhere

I'm bumping up this thread because now, with the greenhouse all closed up for the winter, the plants need to be touched, shaken, stroked and "cooned" more than ever.

I have been regularly shaking the plants or pots since the summer and I think that it helps. (Totally unscientific observation!)

While in the GH today, I noticed that the bench on the far end was vibrating. This bench has a cheapie box fan mounted on it and the plastic blades aren't balanced very well. Maybe I'll put two close to identical plants (Euphorbia obesa) in the same vicinity but one on the vibrating bench and the other nearby.

I do have a pair of Lithops vibrating now in full bloom.

Eons ago when I was an undergrad taking Psych 101 we were told of an experiment done using a plant wired to a lie detector and a match. The readings would go off the scale whenever the match was brought near a leaf and back down as the match was moved away. These results were similar to the ones mentioned above.
I firmly believe that all living things have emotions. What range of emotions I don't know. It may be as basic as "that feels good/bad" but they are still emotions of some kind. I also believe that in some way all living things communicate. This may be a matter of color, shine, how a feather is held or a sound (among many possibilities) but it is communication. When our plants "feel" good they communicate this to us by how they look and whether they produce flowers or fruit for us. A plant that "feels" poorly shows it in the way it looks and only the most unobservant can fail to see that something is wrong.
Touching? I've never heard of that so I haven't been doing it to any great extent aside from when I clean their leaves. I use water and a soft rag to get dust off since a long time ago I read that the dust clogs the plants pores making it difficult for the plant to breath. I do talk to my plants a lot (and many have thought I had a screw loose as a result (lol) and I play music (rock) which they've always seem to enjoy. I'll also dance a bit in the GH and so help me I think they enjoy that too (lol). Maybe it's not the talking, touching, music or dance but our company?

MollyD

Well, here is another take on Cleve Backster, who did the experiments with the match. According to Dr. Backster, plants also react to the boiling of shrimp!

http://skepdic.com/plants.html
http://www.madsci.org/posts/archives/feb98/886113355.Bt.r.html

Now, if you want to read some actual science, here you go:

http://www.imok.ufl.edu/veghort/pubs/workshop/pdf/latimer2.pdf
http://www.springerlink.com/content/64kku776u5319kbj/?p=061853f35f2d4c84ba9242698c6b57d4&pi=0

Wow a lot of great reading there,thanks!

All this makes since to me,my plants react to my pruning right after I bring them into the greenhouse for winter,the
leaves turn yellow and drop on about 1/3 of the leaves on the plant,I know they get less sunlight,one reason for dropping leaves,but what about there reaction to the severe pruing???
We say no fertilzer,for the plants are resting now,but pruning them back,makes them branch out new growth,so that means there must be root growth as well,and in order to support new growth,shouldn't I feed them a little?
I keep several fans on 24/7 at the top of the greenhouse circulating warm air around,then during the day,I run several fans on at ground level,to keep air circulating at soil level,seems to dry the soil faster somewhat in the
containers,but I'm keeping a warmer greenhouse with nite time temps at 60* or more. Daytime temps around 80*
I don't have the time to touch every plant with the human touch,but I mist everyday,and all the palnts have leaves moving from all the fans that are running,and with 5 parrots,that visit the greenhouses with me everyday,they get bird music!!!!
Great thread,hope it continues on!!!

Tman, I'd like to visit your gh everyday too.... Sounds delightful!

Wonderful thread!

I'm one of "the touchers"-personal experience proves(to me, anyway) that plants respond positively.

Over the years, as I've taught many on the care of plants, I've loved to use analogies, such as,"Would you like to take a cold shower?" or "How do you feel, when you are very, very thirsty, or starved?" "How do you feel when you are gently hugged, or patted on the back as opposed to being shoved or slapped?" or "how do you feel about being gently spoken, or sung to, as opposed to being screamed at?"
Well, let me assure you that our plants respond the same as we humans do. They just manifest it, differently.
This kind of reasoning works just as well on 4 yr. olds, to 80 yr. old people.
It's something we can all relate to.
Deanna

DeannaV, I think at first I agreed with your line of thinking and your analogy. Now, not so much.

Consider the term the scientists use, perturb.

Plants apparently like to be perturbed. People, generally, do not (at least I do not).

Plants show greater strength, lower height, and greater disease resistance when perturbed. This perturbation could be manual or in the form of 24/7 HAF fans, or in a larger greenhouse it could be automated mechanical oscillatory shaking (AMOS), mechanical impedence, or mechanical brushing methods.

Now what human likes a fan blowing on them 24/7? What human would like their bed/chair vibrated continuously? Nobody. But plants apparently do.

What human likes to be "rejuvenated" by being off at the ankles so that s/he can regrow more vigorous than before? (OK, well maybe I went too far with that example... :D)

I think we have to be careful with the anthropomorphization that you see in the likes of Backster, Tompkins, and Bird. Pretty soon you are trying to convince yourself that your yogurt has feelings, too (see Skepdic link above). My reading tells me that there is little to no good science to back it up.

But consider why we grow plants and it brings you full circle. We grow plants for our enjoyment, to make us feel better...or to improve our environment, which, in the long run, will make us feel better. Does talking to your plants make you feel better? If so, go for it!

Podster,your always welcome!!!
But if your like me,10 minutes after sitting down in there I get so sleepy,I'm wondering if all the oxygen the plant are releasing is the cause of my drowiness!!!!

more

LOL,LOL stressbaby!!! I was just thinking, that if you could see me outside in the Spring, slapping the bejeebies out of my young trees(to help the sap rise)- or see my vicious(makes my husband shudder) deadheading of annuals in the summer-you would know I was talking in gerneralalities, for the extremely inexperienced gardener.
You know the kind-the ones with the "deer-in-the-headlights" look, when you ask what they know about caring for plants?

Lots of my projects, as a Master Gardener, involved talks to Ladies Church Groups, 4H clubs, etc. However, my favorite and most enthusiastic participants were my little 6,7, and 8 year old
Elementary school students.

I apologize, if I came across,as suscribing to a "pollyanna" approach to growing,only. that was not my intent. :o)
Deanna

No need to apologize, Deanna. If you are helping people understand on some level, and helping them become better gardners, then more power to you.

Now, beating on trees to get the sap to rise... I think I've heard of that, but it takes "touch your plants" to a whole new level.

When I first saw this thread, I was sort of surprised. I am pretty sure that SB is not a commercial grower, and yet the articles that he was referring to apply mostly to commercial growers and I applauded him for reaching out to the more scientific world to grow better plants.
I have read many articles concerning this subject in my trade magazines ( commercial grower here) and what the gist of it is, is that we have to grow many flats of annuals/perennials close together in the grhouse, and often they have to compete for light. The articles were about experiments done on plants in these growing conditions to reduce stretching ( for light) while they are in the growing phase. The results were such that if you can produce some sort of tactile effect on the plants, it would reduce stretching, and make the plants more compact, while still grown close together, and also reduce the need for plant growth regulators. Some growers have taken the experiments to heart and have huge mechanical arms that go across the plants on a regular basis to slow down the stretching. It works. It creates a thicker, stronger stem, but keeps the plant more compact and easier to ship and have a longer shelf life.

I think SB was saying that we should all attempt it in other various ways-using your arm to brush against the tops of the plants on a regular basis ( although I am not sure that if it is not done on a hourly-or close to that-basis, then it may be futile), using fans etc. I think he just likes the word "thigmomorphogensis" -did I spell that right SB??? lol

We people that love to grow do tend to personalize the process, myself included, and I am not sure why. Plants have certain needs in common with animals-water, food, reproduction, proper shelter ( for those of us that are zone pushers-that would be me!! lol) but we do not share the need to express feelings with plants-they don't have them. We do it with other animals as well-my friends will tell you how many times i have said how smart my dog is-well he is smart, as dogs go, but he isn't as smart as I make him out to be!! Cause he is not capable of the level of intelligence/emotions that we humans are. Sometimes I need reminding of that.....lol

Deanna girl!! Stop with the vicious deadheading!! Sounds scary-gardening is supposed to be mediatative...until you get a fungus or burn your plants-been there!!
Anyway, I thought I would throw this perspective in...and I hope everyone gets through this winter in good form, as well as the plants-I say that because I hate winter-the cold, the grey, the damp, the cold ( did I say that already???) lol

Interesting thread! I've just realized my cat perturbs my little ivy topiary in the kitchen window on a regular basis. She jumps up on the shelf it's sitting on (thereby vibrating the plant) and then she loves to rub the sides of her face against the plant. Hmmm..... Should be a very healthy plant!

Well, plants may or may not have emotions, but they certainly have their own consciousness. That consciousness is highly unlikely to be identical to our own, but there will be some correspondences we can recognize if we look.

And, as for deadheading, well, all gardening has as much to do with killing things as it does with growing them. We dig the ground up, killing the plants that were there, we weed, we kill bugs, we thin even the plants we want. As a result, the weeds and bugs might not appreciate our efforts, but hopefully the plants we are trying to help thrive will respond favorably. Even if their intention is to make seeds and our intention is for them to make flowers...

Has anybody read Machaelle Small Wright's work? She really goes way out but is highly successful with her methods.

Dr. Dan Carlson has spent his lifetime researching the effects of sounds on plants and has developed a system of sounds and foliar feeding. To learn what his system entails and the results of his system google sonic bloom and you can judge for yourself.

This message was edited Nov 29, 2006 3:10 AM

Mulchmania-I wasn't clear-my bad! I didn't mean stop deadheading-just stop the vicious mannner...."makes my husband shudder". I was saying that gardening was supposed to be a relaxing event-. I am not against killing plants-I do it all the time, but technically deadheading isn't killing anything-its just getting rid of a part of the plant that is already dead or dying so the plant doesn't try to put its energy into that part of the plant anymore (i.e producing seeds etc)

bluejackalope-I went on his website and read what he said..
did you see this? http://lists.ibiblio.org/pipermail/permaculture/2005-February/021086.html

Referenced rebuttal available upon request, but in summary there is no scientific evidence in peer-reviewed publications that supports the idea that plants respond to sound, voice or music, outside of the vibration referenced above.

And Google search of plant consciousness produces too many references with Cleve Backster for any of them to be taken seriously.

Sorry to be a thread-killer, folks. If you can show me good data, I'll reconsider.

You brut you sb!

I'll buy mechanical conditioning and I'll also buy seismonasty (think Mimosa pudica) but to the best of my knowledge... peer reviewed scientific evidence does not exist supporting a plant having the ability to respond to "sound, voice or music, outside of the vibration referenced above". I believe some people are misinterpreting tropism as well as nastic movements of plants. Plants don't experience fear or joy or anger or any other human emotion. To suggest otherwise is anthropomorphization.

That being said, I love my plants however they are not capable of reciprocity no matter how many times I tell them to grow because Mommy loves them ;)

lol equil.....you are lucky that your plants can't write, or you might be in danger of a autobio written by them called " Mommy dearest". I can only hope that you have a grip on the correct PH for them....and that you have them on the proper fertilization program.

You're right. I only tell them I love them when I have an audience... just call me Joan Plantford.

Maybe you need to hit your plants harder....and take them out of the closest

That's it! They weren't in a closet but they're gonna be now. Bad plants, very bad plants. I'm going out into the garage right now and I'm going to hang them all from (gasp, dare I say it...) cheap metal clothes hangers.

Equil! I hope you're here because they broke ground on your greenhouse!?!?

I was here for the stimulating conversation. Seriously, how can one possibly resist a thread that starts out with "Do you touch your greenhouse plants?" That far too enticing. I simply had to see what was going on.

I was in line for the excavator and then we had that nice cold snap that froze the ground in September. I thought that was perfect because less damage to the ground and all but nooooooo, I'm now backed up to spring. We did select the site though and we did move all the building materials into the storage shed. The storage shed is rather ram packed these days. Just barely made it all in too. That storage shed is only 26' deep.. Does all this activity count for anything or should I go out and hang some more plants on cheap metal hangers?

I'm always touching mine. Looking for bugs, caterpillars and dead leaves. Nice thread! I heard once that the plants under my patio may not grow tall not because of the lack of sunlight but because of lack of air movement. That they would reach for the sun but be spindley because the wind helps the stalk or trunk or stems "know" to get fatter and more substantial. Made sense to me so I got a ceiling fan over them and turn it on hurricane force. LOL They're doing just fine.

Thanks, Maiden!

Here is an interesting study: http://heronpublishing.com/tree/summaries/volume18/a18-65.html

In this study they measured plant (Ulmus) response to differing amounts of stem flexure. The stress of stem flexure helped reduce the plant height and increase stem thickness...but as the amount of flexure increased, the height response decreased exponentially and the leaf surface area decreased.

It suggests that there might be a happy thigmomorphogenetic medium, balancing stem thickness and height against leaf area (and photosynthetic capacity). In other words, a little wind or air movement can go a long way!

And this study suggests that the effect is also present in the roots: http://www.journals.uchicago.edu/cgi-bin/resolve?id=doi:10.1086/320780&erFrom=-4158546030485033797Guest

Well then, sounds like I should turn the fan off gale force... shouldn't I ? LOL Might just want a light breeze under there for bigger leaves. I don't mind that they don't get so tall but it looks nice when they are lush. Thanks for the info stressbaby.