Mimosa pudica is an amazing little plant with some fascinating properties. It is a legume that grows throughout the tropics and is an excellent herb for urinary tract and kidney health. It is often called the sensitive plant because it will respond to touch and other stimuli by closing its leaves. You can find many videos of this behavior on the internet (check them out it is pretty cool to see). The theory is that it does so in order to protect itself from predation.
There is some new research out of Australia showing that Mimosa pudica also has the capacity to learn and alter its behavior. Researches dropped water onto mimosa plants and as expected the limbs responded by folding up their leaves. However, the plants perceived relatively quickly that the water posed no threat and stopped reacting. They had learned not to worry about the water! Those of us in the Pacific Northwest could learn a thing or two from the wise little mimosa. Some plants were able to “remember” this for up to a month.
This ability to learn and retain memory seems to be due to the presence of what are called memristors. Memristors (resistors that retain memory) were created a few years ago out of electronics. These units have now been found in plants. Researchers found that a type of voltage gated potassium channel serves to retain memories for plants. These “memory circuits” have also been found in aloe vera and venus fly-trap species.
We are just beginning to understand the ability of plants to learn. This research helps to shed light on the fact that plants can and do react to and learn from their environment. So pamper your plants; they just might notice and thank you for it!
-  Oecologia. 2014 May;175(1):63-72. doi: 10.1007/s00442-013-2873-7. Epub 2014 Jan 5. Experience teaches plants to learn faster and forget slower in environments where it matters., Gagliano M, Renton M, Depczynski M, Mancuso S.
-  Plant Signaling and Behavior. 2014;9(3):e28152. Epub 2014 Feb 20. Memristors in plants., Volkov AG, Tucket C, Reedus J, Volkova MI, Markin VS, Chua L