The rubber tree (Ficus elastica) is grown as a houseplant rather than outdoors in most of the United States because of its sensitivity to cold weather. When placed in a well-lit, warm area with adequate air circulation and regular applications of water-soluble fertilizer, a rubber tree can outgrow its pot. The tree will need to be transplanted when the roots come out of the soil and begin wrapping around the top of the container.
Prune the rubber tree if needed by cutting back unruly stems to a main limb. Only cut back to the branch collar where the stem meets the limb. Cutting flush or even with the main limb makes it more difficult for the plant to heal.
Lay the rubber tree on its side and gently pull the plant from its pot. If roots have grown through the drainage holes and are preventing removal of the plant, cut off the roots at the drainage holes.
Cover the drainage holes in the new pot with pebbles or small rocks so potting soil cannot become compacted around the holes. Rubber trees will decline rapidly if they sit in water.
Pour a layer of potting soil in the bottom of the new pot, then place the rubber tree in the pot. Add soil and around the sides until the plant's roots are covered and the root ball is at the same level it was in the old pot. Water the plant while adding the soil so air pockets don't form.
Water the plant well and let it drain.