You may wonder what the benefits could be from cloning your tomatoes rather than growing them from seeds, but there are actually a number of them. First, you can clone a tomato plant you know to be sturdy and fruitful for either your own benefit or to share with friends and family. It also means you can clone hybrid tomato plants that do not grow from second-generation seeds. It is also much faster than growing from seeds and it increases the chances that your plants will establish themselves successfully in soil, thus producing more fruit by the end of the season.
You must first find a large, established branch. Branching off of these will be smaller branches that create a V shape between the stem and the branch. These are called suckers and they are ideal to clone because they are not fully grown yet and are capable of growing more leaves. Established branches will not be able to form a separate tomato plant. Be careful when snapping off the smaller stem, you don't want to damage it.
Afterwards, take the stem, dip it into water and then a rooting hormone before planting in potting soil. The leaves should be an inch above the soil, so plant accordingly. Once you have filled in the holes, you will need to generously water. You mustn't allow the stems to dry out at any point in time, this will prevent the plants from establish deep root systems, which will ensure their success when you transplant them outside. You should care for them in the same way you would care for a newly sprouted tomato plant that you have grown from seed or purchased from a nursery. The cuttings will normally take 4 weeks before they are ready to go outside and be placed in your yard.