I have a special fondness for this plant. Growing up, we had a large "rubber tree" in our house. This plant seemingly thrived every kind of neglect. It was watered unevenly, it got moved all over the house, its light wasn't great...and yet it seemed to survive for years. Then, one month, it just didn't survive anymore. All the leaves dropped and the plant died. I still don't know what killed it (I wasn't the one taking care of it, so I have no idea who was doing what), but I do remember feeling like there must be SOME way to save this odd-looking plant, with its huge, soft leaves and slightly exotic name.
If I had to guess, I suspect it was finally the lack of water that did it in.
F. elastica is a subtropical to tropical plant that comes from Southeast Asia. There, it can grow to 50 feet with an enormous canopy of draping, foot-long oval leaves. Like many ficus, they have hanging roots and develop flanged trunks over time. In the home, F. elastica is an excellent standard plant that thrives with bright light, regular water, warmth, and lots of fertilizer.
Light: F. elastica require bright, filtered light and can tolerate morning sun. Plants that are kept too dark will become leggy, lose their lower leaves, and the color will become dull instead of glossy and vibrant.
Water: Keep steadily moist; they are vulnerable to excessive dryness.
Soil: Any good, fast-draining potting soil will likely do.
Fertilizer: Feed with a weak liquid fertilizer throughout the growing season. They are relatively heavy feeders when healthy.
Rubber plants can be propagated from leaf-tip cuttings, but it's not particularly easy. It's probably better to just buy a potted plant. If you attempt to take cuttings, use a rooting hormone and be vigilant about high humidity and plenty of warmth. Don't be discouraged if they don't propagate easily; it's an inexact science that takes some time.
F. elastica grow fairly quickly under good conditions and will need to be repotted every year until the plant reaches its desired size. Larger plants can be difficult to repot so if you can't move the container, scrape off a few inches of potting media and replace with new potting soil. Some experts recommend only lightly fertilizing indoor plants to prevent stretching and the plants becoming root bound because they grow too fast.
The most common F. elastica is the 'Decora' cultivar. This is the familiar rubber tree with glossy green leaves with a slight reddish or bronze cast to the undersides of the leaves. In general, F. elastica is bred for larger, more glossy leaves.
As I mentioned, these are not particularly difficult plants. Successfully growing one generally means finding the right balance in your environment: light but not too light, moist but not wet, enough fertilizer to keep it healthy but not too much to encourage fast growth. Like other types of ficus, they are vulnerable to cool drafts. Plants that are suffering for whatever reason will become leggy, with stretching internodes, and the leaves might first turn yellow and then brown and then drop off entirely.
F. elastica look their best when fully clothed with leaves, so take any leaf yellowing seriously (although once a leaf starts to yellow, it's most likely gone already). If the leaves look full and are drooping, your light levels are probably too high. Ficus elastica are vulnerable to pests including aphids, mealy bugs, mites, scale, and white fly. If possible, identify the infestation as early as possible and treat with the least toxic option.