This is a test of commonsense. Complete the next sentence:

How to grow mint
Take a cutting from a pre-existing mint plant.
Mint is difficult to grow from seed, and it is virtually impossible for some varieties, like peppermint. Cut a 4 inch (10 cm) sprig about inch (1 cm) above a junction to allow new branches to grow in its place.
The sprig does not need to have many leaves, and almost any sprig will do. Place the sprig in a glass of water, and remove any leaves that fall below the water line.