Bananas last 30 seconds before rotting instead of 15.
~ BTD6 descirption
Long Life Bananas is the first upgrade on Path 2 for the Banana Farm in Bloons TD 5. This upgrade makes the bananas produced from the banana farm stay on the screen for 20 seconds instead of the usual 10 seconds (25 in all Mobile versions). It is useful for people who don't want to place their mouse over the Banana Farms all the time and for people that use Dartling Guns.
It also appears in BTD6 also as the first upgrade on Path 2. This upgrade turns the bananas green, making them last longer too, for 30 seconds instead of 15 seconds for normal bananas. It costs cheaper, at $255 on Easy, $300 on Medium, $325 on Hard, and $360 on Impoppable.
However, if you are unable to use Monkey Farmers due to agents/powers being disabled, it might be fine to get this upgrade to have more time to pick up bananas, especially if the player has tens of Banana Republic or Banana Plantation farms.
Do not use this with Marketplace, as it does nothing to enhance the Marketplace in any way, wasting money.