|If you want power, it is only some Adam away.|
"My daddy's smarter than Einstein, stronger than Hercules, and can light a fire with a snap of his fingers! Are you as good as my daddy, mister? Not if you don't visit the Gatherer's Garden, you aren't!" (Quoted from the Gatherer's Garden machine when walked past)
The Gatherer's Garden is a vending machine which can be found multiple times throughout your adventure through Rapture. These vending machines sell plasmids, gene tonics, and extra plasmid slots and gene tonic slots. To buy from these machines, you need to exchange ADAM, which can be extracted from Little Sisters.
Different Gatherer's Gardens have different plasmids for sale. Upgraded forms of plasmids become available after more basic ones are purchased.