Basil, Like Many Other Types of Herbs, does not Like It When the Temperature is on the Cool Side.
In contrast to many other types of herbs, basil won’t survive being kept in the refrigerator. Basil has the potential to become black when it is exposed to an excessive amount of moisture. If you put fresh basil in the refrigerator while it is still growing, it will turn brown and wilt.
The ideal conditions for basil are mild temperatures and bright sunshine. Place a plant in a container and place it close to the sink so that the plant can drink some of the water that is drained from the faucet. Make sure the water in the bowl is at room temperature, then arrange the fresh basil leaves in the water as you would flowers.