The Ficus Elastica, otherwise known as the rubber tree or rubber plant, is a popular plant for indoor and outdoor gardening across the United States. The rubber tree gets its name due to the thick, sticky, white latex that bleeds from the fleshy leaves if you snap them apart.
Latex rubber is in high demand, and there are giant rubber tree plantations in Southeast Asia and Africa to cater to the needs of the rubber industry. When rubber trees grow in a natural environment with optimal growing conditions, they can reach heights of up to 100-feet.
The dark green, waxy leaves develop deep red or purple coloring on the tips, depending on the age of the plant, and the time of the year.
Rubber plants do well indoors and outdoors, provided gardeners offer them the proper growing conditions. These trees are relatively hardy, and established plants can survive cold winter nights without protection.
In the United States, rubber trees suit gardens in USDA Zones 9 to 11. These trees enjoy warm climates, and if you want to grow them in the northern states, you’ll need to bring them indoors. Indoor rubber trees still grow vigorously and can reach 6 to 10-feet tall with ease.
The indoor gardener will need to keep pruning the plant back to prevent it from getting out of hand. The same applies to outdoor rubber trees. Rubber trees planted next to walls and other trees can become invasive as they get large. They’ll push over fences, and the roots break up driveways.
Popular varieties in US gardens include the “Burgundy” or “Black Prince.” In this guide, we’ll give your everything you need to know about growing rubber trees indoors or outdoors.
How Do I Care for Rubber Trees?
- 1 How Do I Care for Rubber Trees?
- 2 What Soil Conditions Suit Rubber Trees?
- 3 Can I Plant Rubber Trees Outdoors?
- 4 What Lighting Conditions Are Best for Rubber Trees?
- 5 How Do I Water Rubber Trees?
- 6 What are the Humidity and Temperature Requirements for Rubber Trees?
- 7 Are Rubber Trees Toxic?
- 8 How Do I Propagate Rubber Trees?
- 9 How Do I Prune Rubber Trees?
- 10 What are the Pests and Diseases Affecting Rubber Trees?
Rubber trees grow aggressively in the right climate conditions. These trees need a good balance of sunlight and water to grow. If the leaves of the tree start to droop, it’s a sign they need more water. Overall, rubber trees are very hardy plants, and they can persist in drought conditions for months.
Rubber plants are easy to care for, and the most amount of work they provide for the gardener comes with the pruning of the tree.
What Soil Conditions Suit Rubber Trees?
Rubber trees will grow readily in a variety of soil types. They prefer slightly acidic soil, but they do well in most soil conditions, provided there is adequate drainage.
When planting your tree, make sure that you dig a hole that’s big enough to accommodate the root ball. Don’t plant too deep, as this may cause the tree to die back.
You won’t need to add any amendments to the soil, and the plant doesn’t require the use of fertilizer in the growing season. You’ll struggle to contain the growth of the tree as it is, but the addition of compost can make things get out of hand in your garden.
Can I Plant Rubber Trees Outdoors?
Rubber trees do well as indoor and outdoor plants. If you’re planting outdoors, then you’ll need to use a part of the garden that gets direct sunlight for at least 6 to 8-hours of the day. The more sunlight you give the tree, the faster it grows.
Outdoor rubber trees grow to tremendous heights without any pruning. Make sure you don’t plant them near walls or other trees, as the heavy branches might cause the structures to collapse and crowd out your other plants.
What Lighting Conditions Are Best for Rubber Trees?
Rubber plants thrive in natural habitats that have plenty of sunlight and water. It’s for this reason that farmers grow them in large crops in Africa and Southeast Asia. If you’re growing a bonsai variety, then you can leave the pot in indirect sunlight in a bright room in your home for the best results.
Direct sunlight may scorch the leaves of juvenile trees of bonsais, but the plant recovers quickly with the right watering and care.
The variegated varieties of rubber trees require more light to maintain the color in the foliage. Place these trees in full sunlight for best results.
How Do I Water Rubber Trees?
Rubber trees get very thirsty during the summer months, especially in hot climates. Gardeners need to ensure that they keep the soil around the roots moist at all times, but don’t saturate the roots too much.
Waterlogging the soil around the roots can invite the onset of root rot ion the plant. Rubber trees with root rot will start to drop the leaves, and turn color. If you’re growing your rubber tree indoors, then wipe the dust off of the leaves once a week to help the plant absorb more sunlight.
Rubber trees also enter a dormancy period during the winter. When the plant goes dormant, don’t water it until the early spring. The dormancy helps the plant recover from the stresses of the year. If the leaves of the plant start to droop during dormancy, give it a little water, but not much.
As mentioned, mature rubber trees are hardy and drought-resistant, making them a good choice for gardens in the Southwestern United States.
What are the Humidity and Temperature Requirements for Rubber Trees?
Rubber trees thrive in temperatures of between 60F to 85F. These trees can accommodate reasonable levels of cold temperatures, but when the mercury drops below 60F, they require some protection to help them stay warm in the cold.
If you live in a colder region of the United States, we recommend you mulch around the base of the plant during the late fall. The mulch helps to protect the roots from the cold. If it gets below 50F, then wrap the tree in burlap if it’s outdoors.
If you’re growing your rubber tree indoors, then keep it away from drafts and doorways. The wind chill and drafts will stunt the tree’s growth.
The rubber trees grow well in humid environments, like those in their native lands. However, these trees also survive at high and dry altitudes where the relative humidity is low. Rubber trees prefer consistency in temperatures, without wild swings in conditions between the seasons.
Are Rubber Trees Toxic?
Rubber trees are not toxic plants. However, if you cut the stems and snap apart the leaves, you’ll notice that they bleed a milky-white substance. This latex is in high demand with rubber manufacturers all around the world, and it’s a base ingredient for many different industrial rubber compounds.
If the sap gets onto your skin, it might cause mild irritation if you have a sensitivity or an allergy to latex. Eating the parts of this tree could end up in a trip to the emergency room.
How Do I Propagate Rubber Trees?
It’s easy to propagate rubber trees if you know what you’re doing. There are two propagation methods proven to work. The first method is through taking a cutting from the tree.
Cut a branch at a 45-degree angle, and then leave it to bleed out. Once the latex dries up, place the limb in some water, covering the bottom of the branch. You should start to notice new roots emerge in a few weeks. After the roots begin to show, plant the tree in the flowerbed or a pot.
The second propagation method involves cutting the branch 80% of the way through. Force a toothpick into the cut, and then pack in and around the wound with moss.
Cover the moss and tree branch using plastic wrap, and leave it for 2-weeks. When you start to see, the new roots emerge through the moss, cut the branch off of the tree, and plant it in a prepared container or flowerbed.
How Do I Prune Rubber Trees?
As mentioned, rubber trees grow aggressively, even in the absence of nutrition in the soil. If you’re growing your rubber tree outdoors in the garden, then you’ll need to prune it back in the middle of the growing season, and at the end of the late fall.
The pruning encourages new growth, so make sure you sculpt your tree away from any walls or other trees.
When pruning, make sure you use a sharp saw for outdoor trees or a sharp pair of scissors for indoor rubber trees. Always wear protective gloves when pruning to avoid getting the liquid latex on your skin.
What are the Pests and Diseases Affecting Rubber Trees?
Rubber trees are hardy plants, and they don’t attract many pests or diseases, indoors or outdoors. If you’re planting in the garden, then look out for infestations of mealybugs and aphids during the early summer months.
Scale can also be a problem and may cause the leaves of the rubber tree to wilt or droop. If you catch the infestation early, remove the bugs with your fingers. However, if the infestation is heavy, then spray your tree with an organic pesticide like neem oil.
To prevent root rot in your rubber tree, make sure you let the soil dry out between waterings, but keep it moist under the surface. Spider mites lay eggs in the dry soil, increasing the pace of the infestation.