Rubber trees can grow out of cut stalks. This is one of the most common methods to create a new rubber tree. First cut a small part of the stock and leave it in water. Soon enough, i.e., in a few days you should see some roots come out. Now you should transfer it into a pot where it will grow. The soil should be such that it can provide good drainage. Do keep the young tree away from the sun as they do not like the hot sun, especially when new leaves come out, they should not be exposed to sun if you wish to make them bigger. Keep the tree moist during spring and summer when it is their growth time, and relatively dry for the rest of the year. As the trees tend to loose their leaves that are at the base, cut them if you see that these are drying up and getting ready to fall. New leaves may come out from the same places.