Friday, April 19, 2013

On the subject of what ARE your plants thinking...

I suppose that before we can talk about WHAT plants are thinking, we need to consider IF they think.  You may think it's pretty obvious that they don't - no one has ever found anything even remotely resembling nerves or brain in any plant anywhere.  Have they?

Since definitions of thinking mostly involve mind (generally understood as brain) and/or acts of contemplation, imagination, decision, movement and so on, right there, plants are exempted - and plants are quite obviously rooted in place, so are unable to perform "acts" of any kind, right?

Well, okay, they do grow, and turn toward the light, and sometimes tendrils can wind around things, and some petals can close at night...but those things are all just cellular responses to simple stimuli like light and touch, right?

They're not "acts" like when you decide to go somewhere so you move your muscles and you get there.  Leaves move when the wind blows them, but that's just moving because the wind is moving, nothing to do with action or volition or anything like that, right? The other kinds of movement you see in plants is pretty much the same, right?

Well maybe...and then again, maybe not.

Let's think about it <<<>>>> what exactly are we doing?  What is "thinking" anyway?  We're pretty sure it's occurring in our brains; we know from imaging and scanning that certain parts of our brains "light up" when we think of certain things, or think about them in certain ways; and we know that if brains are injured, some types of thinking can be changed or cease to function.

But consider wasn't so very long ago that people had no idea what all that mushy stuff inside heads was for.  If they thought about it at all, they thought that thinking originated in the heart, or maybe the solar plexus - that old "gut feeling," you know?

If you come right down to it, we don't REALLY know what's happening in the brain, how the electronic/chemical stimulation of cells interacts in a perception/memory/integration/abstraction interface to produce thought and action, whether it be the simple thoughts of a worm, or the towering thoughts of a human being.  Some theorists are even beginning to wonder if "thinking" might be going on at the molecular level, or even the quantum level, and that the brain is simply a switching station.

Back to the original question - do plants think? (By the way, this is a really huge topic, and I'm going to be batting it around for a long time, so if anyone else has any thoughts/information, feel free to throw them in.)  Let's define thinking (at least at this point) as the  process of acquiring information from/about the outside world by the stimulation of certain receptors (cells or aspects of cells, probably), that information then translated (somehow) into actions that allow the organism to respond (somehow) to the outside world in ways that are contributory (hopefully) to its survival.

By using this kind of definition, I'm getting away from the idea that "thinking" necessarily involves "words."  It does, however, involve ACTIONS based on INFORMATION.   Plants definitely acquire/take in information, (something to talk about at a future time,) but do they actually perform any actions, other than simply "growing?"  (Which isn't so simple, when you come down to it.)

Other than those few things I mentioned earlier, what kinds of actions could they possibly perform?  Well, in order to understand plant movement, you need to adjust your own perceptions.

Ever seen those fast-action films of plants growing and flowers opening?  In them you see that plants move to the beat of a drum different than that which animals follow. 

As you slow down to their score and measure, you see the twigs and buds on trees and bushes swinging in slow circles,  leaves on plants below moving up and down as their growing tips quest 360 degrees around, flowers bending and shaking, stems trembling toward unseen supports and sending out tendrils that dance complicated patterns until they encounter something to grab onto, at which point they quickly pull the rest of the plant to themselves.

Beneath the ground, tiny rootlets burrow through the earth, tasting for moisture and nutrients, responding to the pull of gravity, possibly other imperatives known only to the plants.  Seeds burst open, roots hurrying down, stems shooting up in frantic haste to reach the light.

  The movement of the stomata on leaves as they transpire air into and out of the plant, when speeded up, looks remarkably like  breathing...probably because it is breathing.

Then there are the incredibly fast movements (fast enough for us to see in real time, which means really really fast in plant time) of carnivorous plants closing on their prey, or the Mimosa pudica folding its leaves when they are touched.  Some plant tendrils respond to weights as slight as .00025 of a gram.   How can they do these things when the have no nerves to transmit stimuli, and no muscles to contract tissues?

In my next post on this subject I'll speculate some more about plant actions, and also how they might acquire and process information about their environments.  Leaving you with an interesting little video...

Some links to other videos of plant movement:

Major source material, The Secret Life of Plants  by Peter Tompkins and Christopher Bird.  Available from Amazon.

                                                                (by Marlie Graves)

Friday, April 5, 2013

Pruning that ceiling-hitting plant on my Pinterest board Home Interiors with Plants on 4/5/13

So sorry there's no pic - you'll just have to refer back to Pinterest.  I tried for 30 mins to find the original page, or to find some way to copy from my pin, all to no avail.  And I have a rule, which is no more than 30 mins devoted to fruitless searches.  Ergo, after 30 mins, no pic.  But I directed folks here for a discussion on pruning the darn thing, so discuss I shall.

As best I can tell from that one picture, the plant is a Dracaena tarzana.  It's often hard to tell from just one shot what exactly a plant is, but even if it's some other kind of dracaena, even some kind of yucca, the culture and pruning practices are the same.

The first thing to decide before you set out to prune a plant is 'how do I want it to look when I'm done?'  The choices here would be tall, or short, and one cane, or more than one.  (The long trunky, or stemmy thing is actually called a cane in these type of plants.)  I think I'll describe the procedures for each of these choices in turn.

Before I begin, let me note that cane-type plants are great to do these kinds of procedures on, because they are so vigorous, and can sprout from dormant buds even when they appear to have been dried out and dead for years.  One time I built a short, decorative fence by embedding a bunch of old corn plant canes in the ground.  Don't you know, after about six months, my fence began to sprout!  But I digress.

The elegant, horticultural thing to do would be to air layer.  Arm yourself with a sharp knife, some damp sphagnum moss, some plastic wrap, rooting hormone, and electrical tape.  Pick the point where you want the roots to start growing, say about seven feet from the top of the plant - that will give you a six foot tall plant after it's potted.  Oh yes, don't forget to sterilize the knife with dilute bleach solution.  Now, scrape away the top of the bark all the way around the cane, in a strip about 1" wide.  Gently, now, only the very top part, the  skin, so to speak.

Uh-oh, uh-oh, I hear some of you starting to cringe.  Cutting?  MY PLANT???  Okay, here's what you need to understand - cutting a plant, in terms of pain to the cuttee, is approximately the same as cutting your hair or fingernails...There.Is.None.  It makes the plant more beautiful, if you do it right.  If you don't, the plant just keeps on growing, and you get to try again another time.

Back to scraping the top layer of bark.  After you've done that, rub a bunch - maybe 1/2 teaspoon - of the rooting hormone into the scraped area, and wrap it with moss.  The moss should be damp, but not soaking - squeeze out all the water that will go.  Wrap it into a nice fat clump all around the cane, then wrap plastic wrap around that, and secure the top and bottom tightly with the tape.  There.  You're done.  Don't you feel accomplished?

Now, you and your plant just wait for a few months.  Just keep an eye on the moss, if you see it's starting to look dried out, undo the tape and pour in a couple of spoons of water.  But it should stay moist until the roots grow.  If you want to see what all this looks like, try

When the roots have nicely filled the bag of moss, cut the cane below the moss bag to free your now-shortened plant.  This is probably the hardest part of the process, because some canes are thick and quite hard, and you may have to use a hand saw to do the cutting.  Pot the plant with its new roots and shorter cane into your pre-selected beautiful container, or even better, into a plastic grow pot that you can place into your pre-selected beautiful container.  This is called 'double potting,' and I have a video about that at

A word about soil.  Please don't use those "moisture-retentive" mixes that some manufacturers are marketing.  They do retain moisture, but that's a bad thing, because too much moisture in the soil is what kills most indoor plants.  Use a cactus mix if you want, or a "soilless mix" if you can find it, or do some research and make a nice chunky, porous mix of your own.   Try this  to start research.

If your plant is already 10' tall, though, I think you probably have a good handle on its cultural requirements, and you already know about porous mixes and not overwatering, so I'll return to the pruning stuff.   Now, if you want your plant to end up short, say 3 or 4 feet,  do the air layering thing much closer to the foliage head; remember, you'll eventually be sticking about a foot of the cane-with-roots into the pot.

But what about the multi-cane thingy?  This involves the not-difficult strategy of sticking one end of the cane, or piece of cane,  into moist soil, and then being patient.  As long as the soil is kept barely damp, the cane should  sprout - not always, not every one, but a surprisingly high proportion of the time.  In fact, you don't have to air layer at all, you can just cut the cane below the foliage, then bury the cut end in the soil.  It's best to air layer a valuable plant, though, because roots might not form quickly enough to support all those beautiful  leaves.

So okay,  back at the big tall plant (or short, fat plant, if that's the way you shaped it) that you air layered into  its new version, you've still got a long bare cane sticking out of the pot.  Left to itself, it will probably sprout a bunch of new leaves, and keep right on growing.   Or you could cut the long cane into 2 or 3 pieces - different lengths look best- put them back into the soil with the rooted piece, and see what happens.  You can even cut the long cane into very short pieces, about 2" -  each piece needs at least 1 scar where a leaf used to be - lay them horizontally under the soil, and wait for them to sprout.

So you can make yourself two new plants from the old one, or a whole bunch of new year's Christmas presents for all your friends!  Please don't be afraid to prune.

Till next time,
Marlie - The Ficus Wrangler
                                                                                               (by Marlie Graves)