From what I have read around the internet, one of the main causes for this is improper plant nutrition of some kind. It is happening to me right now because I used too much MiracleGro, so the plants were getting too much nitrogen, which caused some yellowing of the leaves and the falling leaves and flowers. I ran across this site, which might be helpful to you, they talk about this very thing, and someone was successful in saving their plant by using an epsom salt and water mixture.
http://forums.gardenweb.com/forums/load/pepper/msg0614591310637.html
It has lack of water.
ethylene
From what I have read around the internet, one of the main causes for this is improper plant nutrition of some kind. It is happening to me right now because I used too much MiracleGro, so the plants were getting too much nitrogen, which caused some yellowing of the leaves and the falling leaves and flowers. I ran across this site, which might be helpful to you, they talk about this very thing, and someone was successful in saving their plant by using an epsom salt and water mixture. http://forums.gardenweb.com/forums/load/pepper/msg0614591310637.html
Yes some plants have leaves which fall of like mango leaves . But there are some plants of which leaves do not fall , like oak leaves.
These plants are called evergreen plants
Gravity
Gravity
Gravity
Bougainvillea plant fall their leaves during a hot day.
They are called "evergreen" plants but the leaves do fall down and get replaced, just not all at once.
they fall off
To grow a needs leaves.
we get oxygen from plants that live during the winter such as pine tress
What causes trees to lose their leaves in the fall