The rubber tree (Ficus elastica), is a popular houseplant with large, glossy, and leathery leaves. It is native to the tropical regions of Southeast Asia, particularly Indonesia and Malaysia. The plant belongs to the Moraceae family, which also includes figs and mulberries.
It has become naturalized in Sri Lanka, the West Indies, and the US state of Florida. Despite its common names, it is not used in the commercial production of natural rubber. The tree can grow up to 100 feet tall in its native range, though it is closer to half that size in home gardens. Due to its frost intolerance, rubber tree is often grown as a houseplant.
The rubber tree has been cultivated as a houseplant for over a century, with its popularity rising in the Victorian era due to its attractive foliage and ease of care. The plant’s large leaves can be dark green, burgundy, or variegated, depending on the variety. This plant is also referred to by names including: Ficus elastica, the rubber fig, rubber bush, rubber tree, rubber plant, or Indian rubber bush, Indian rubber tree.
Most rubber plants (Ficus elastica) grow as houseplants because they require warm temperatures year-round to thrive. They survive outdoors in U.S. Department of Agriculture plant hardiness zones 10 through 12, where temperatures rarely drop below 60 degrees Fahrenheit. Rubber plants grow well as large potted plants, growing 6 feet or taller if left unpruned.
Characteristics of Rubber Plant
- Lifespan: The plants can live for many years if properly cared for. With the right conditions, they can grow up to 100 feet tall in their natural habitat. As a houseplant, they reach a height of 6 to 10 feet.
- Branches: Feature thick, woody branches that can support the weight of their large leaves. Pruning can help maintain a desired shape and size.
- Growth habit: Grow upright and can become quite tall. They can be pruned to maintain a more compact shape, especially when grown in a container.
- USDA zones: The plants are hardy in USDA zones 10 to 12, where they can be grown outdoors. In other zones, they are usually grown as houseplants.
- Sap: Rubber tree plants exude a sticky white sap whenever branches or leaves break. This sap can irritate the skin, and if eaten, cause indigestion.
- Bark: The bark of the plant is smooth and gray in color. It can be easily damaged, so it’s important to handle the plant with care.
- Root system: They have a strong root system that can become invasive if not kept in check. In their natural habitat, they can grow large and sprawling, but as a houseplant, they can be kept in a container to control their growth.
- Leaves: They have large, thick, and glossy leaves that are dark green in color. The leaves are oval-shaped with pointed tips and can grow up to 12 inches long and 6 inches wide. New leaves are reddish or bronze in color before maturing to green. Some varieties may have variegated or burgundy leaves. The leaves are arranged alternately on the stem.
- Flowers: They rarely flower when grown indoors, but in their natural habitat, they can produce small, inconspicuous flowers.
- Climate: They prefer warm, humid conditions and do not tolerate cold temperatures well. They thrive in temperatures between 60 and 80 degrees Fahrenheit.
- Soil: Plants prefer well-draining soil that is rich in organic matter. They can tolerate a wide range of soil types, but do not like to be waterlogged.
- Watering: Rubber plants prefer to be kept consistently moist, but not waterlogged. They should be allowed to dry out slightly between waterings. Overwatering can lead to root rot, while underwatering can cause the leaves to wilt and drop.
- Fertilization: They should be fertilized once a month during the growing season with a balanced, water-soluble fertilizer.
- Pruning: Can be pruned to control their size and shape. Pruning should be done in the spring or summer when the plant is actively growing.
- Propagation: Can be propagated from stem cuttings or air layering. Stem cuttings root readily in water or soil. The cuttings should be taken in the spring or summer and allowed to root in water or moist soil before being transplanted into a pot.
Varieties of Rubber Plant
| Variety | Description |
|---|---|
| Ficus elastica ‘Robusta’ | The most common variety, with large, glossy, green leaves. |
| Ficus elastica ‘Tricolor’ | Variegated with cream, pink, and green leaves. |
| Ficus elastica ‘Decora’ | Feature dark green leaves and a dense growth habit. |
| Ficus elastica ‘Burgundy’ | A dark-leaved variety with reddish-green foliage |
| Ficus elastica ‘Melany’ | A dwarf variety with smaller leaves. |
| Ficus elastica ‘Tineke’ | Variegated with creamy white and green leaves with a touch of pink. |
| Ficus elastica ‘Abidjan’ | A dark-leaved with reddish-green foliage similar to ‘Burgundy’. |
| Ficus elastica ‘Doescheri’ | A variegated variety with creamy white and green leaves with a touch of pink. |
| Ficus elastica ‘Ruby’ | A red-leaved variety with bright red foliage. |
| Ficus elastica ‘Yellow Gem’ | A rare variegated variety with yellow and green leaves. |
| Ficus elastica ‘Black Prince’ | A dark-leaved variety similar to ‘Burgundy’ and ‘Abidjan’. |
Growing Rubber Plant Indoors
Rubber plants benefit CO2 and oxygen balance when growing in the house. Like most plants, an indoor rubber shrub will consume carbon dioxide in the room and convert it into fresh oxygen. The plant “breathes” in carbon dioxide present in the air and reacts it with the water from the solid to create byproducts that the plant needs – and oxygen. While many plants go through this cycle, the rubber plant is a very efficient converter and creator of oxygen due to the large surface area of its leaves and the way it can also remove harmful contaminants while creating only oxygen as a byproduct.
Care guide
- Place the potted rubber tree in a room that maintains a constant temperature of 60 to 75 degrees Fahrenheit. Position the plant in bright, indirect sunlight and away from heating and cooling vents. Rotate the plant one-quarter of a turn every one to two weeks to promote even growth.
- Water the potted rubber tree when the top 1 to 2 inches of soil becomes dry. Fill the pot full of 100-to-110-degree-Fahrenheit water from a watering can. Wait for the water to drain into the soil completely. Fill the pot a second time with water. Discard any standing water in the pot’s drainage tray if applicable. Never over-water to the point that the soil becomes soggy.
- Mix 1/2-teaspoon 10-10-10 nitrogen, phosphorous and potassium water-soluble fertilizer with 1 gallon of water in a watering can. Apply the fertilizer every three to four weeks to the rubber tree during its active growing season. Fill the pot full of fertilizer solution and wait for it to soak completely into the soil. Fill the pot a second time. Discard any solution collected in the pot’s drainage tray. Apply the fertilizer in place of watering. Stop fertilizer the plant once its growth slows and stops in the fall and winter.
- Cut off any dead or broken branches with a pair of pruning shears as soon as they appear. Make the cut 1/4 inch above a lateral branch, leaf petiole or growth node. Cut off any yellowing or dead leaves as they occur. Trim back vigorously growing shoots to encourage lateral branching and maintain the plant’s appearance.
- Check the rubber tree’s leaves and stems for green-bodied aphids, spider mite webbing, round brown scales or waxy white mealybugs each time you water. Mix 2 tablespoons of neem oil with 1 gallon water in a tank sprayer or spray bottle. Spray infested foliage and stems with the solution, coating all surfaces completely. Repeat the application every one to two weeks until the insects disappear.
- Wipe the plant’s leaves with a damp cloth to remove dust, dirt and debris. Clean the plant’s foliage every two to four weeks to prevent buildup on the leaves.
- Repot the rubber tree once it outgrows its current pot and its roots become crowded. Fill a plastic pot that is 2 inches larger than the current pot, half full of potting soil. Only use a pot that has drainage holes. Slide the plant from its current pot, spread its roots outward gently and place it in the center of the new pot. Adjust the soil level to position the root ball’s top 1 to 2 inches below the pot’s top. Fill the pot with soil, tamping it down around the roots. Do not plant the rubber tree deeper than it was previously growing. Water the pot, moistening the soil completely.