How to Plant, Grow, and Care for Indoor Orange Trees
If you live in a colder climate that takes citrus off your growing list or don't have the space to grow citrus outdoors, try growing orange trees indoors instead. Houseplant expert Madison Moulton covers the essentials you need to grow (and harvest from) indoor orange trees.
If your garden is too small to grow your favorite citrus variety, or if you don’t have any outdoor garden space, growing an indoor orange tree is the solution.
Several orange varieties remain compact and are happy to grow in containers indoors. The calamondin orange is the most popular, but you can keep a few other compact oranges in your indoor garden year-round.
To harvest citrus indoors or simply grow them for their lush, glossy leaves, follow these steps.
Orange Tree Plant Overview
Plant Type Tree
Species Citrus x sinensis
Native Area Southeast Asia
Exposure Full sun
Height Up to 6′ indoors
Watering Requirements Moderate
Pests & Diseases: Scale, root rot, powdery mildew, citrus canker
Soil Type: Well-draining citrus potting mix
Toxicity Toxic to pets
What Is It?
Orange trees are part of the Citrus genus, known for tart flavors and juicy fruits. The most common species is Citrus × sinensis, but hundreds of different orange varieties are grown worldwide.
These evergreen trees can reach over 30 feet tall outdoors if given the space. However, they will remain far more compact when confined to a container and exposed to differing conditions indoors. The glossy green leaves, adorable white flowers, and (of course) the iconic orange fruit make these trees a wonderful attraction to grow indoors.
Orange trees are native to Southeast Asia. They thrive in warm, tropical, and subtropical climates and require a minimum temperature of around 50F to survive. As many parts of the US experience much colder winters than what orange trees are used to, our homes (or greenhouses) provide the ideal protection, whether you’re growing them indoors year-round or simply bringing them inside when temperatures drop.
There are several citrus varieties suitable for indoor gardening thanks to their compact size:
- Calamondin: The most commonly grown indoor orange, with small and tart fruits perfect for marmalades.
- Tangerine: Similar in flavor to oranges and compact, ideal for growing indoors.
- Valencia Orange: Develop sweet oranges that are perfect for juicing. Slightly taller than other compact varieties.
These trees easily fill corners with lush leaves that add a tropical touch to any room. And as a bonus, they release a citrusy scent when in flower. As long as you can provide the right environment, you’ll also harvest delicious fruits straight from the tree indoors.
How to Grow
Growing orange trees indoors is slightly different from the regular houseplant care routine you may be used to, especially if you want them to produce fruits. They are not tricky to grow in the right environment, but they are not completely hands-off houseplants.
The right care starts with choosing the right variety. Size is important (look for trees labeled ‘dwarf’ or ‘semi-dwarf’). However, you must also look for oranges that don’t mind being confined to a container and can handle a little less than all-day full sun.
Don’t just pick up any orange tree you see at your local nursery and pot it up to grow indoors – check what you’re buying first to make sure it will be happy there.
Once you bring your tree home, place it in the perfect environment and keep up with care year-round to ensure you enjoy the fruits of your labor.
Orange trees require direct sunlight to produce fruits. They can handle slightly less sun if you’re happy to enjoy them for their foliage alone, but if you’re looking to grow a productive tree, full sun is essential.
This is much harder to find indoors than outdoors. You must choose a sunny spot right in front of a window, giving the tree at least four to six hours of direct sun daily. A south-facing window is best for this, maximizing the hours of direct sun your orange tree receives.
Consider the height of the tree and the angle that the sun hits. There is no use placing the plant in front of a sunny window if that sun is not hitting the leaves directly. If you have a smaller tree, lift it using a pot stand to boost direct sun exposure.
If you can’t find the ideal placement, supplement with grow lights to get the most out of your indoor orange tree. Also, don’t forget to rotate the pot every week to ensure that all sides of the tree receive equal sunlight exposure.
Your indoor orange tree will only be able to develop juicy fruits (or any fruits at all) when it receives enough water. Regular watering, especially when temperatures are high, prevents stress and ensures the tree has all the resources it needs to grow successfully.
Water often, allowing the soil to dry out slightly between waterings to avoid oversaturating the soil. The watering level will depend on a few factors, such as the size of the pot, the growth rate of the tree, and the humidity levels in your home.
Rather than following a strict schedule, make it a habit to check the moisture levels regularly and water again when the top half of the soil dries out. You probably need to increase your watering if you notice any yellowing and wilting. If the soil stays soggy and leaves start to drop off, you might be overwatering.
If your orange tree came in a pot, avoid repotting for a couple of weeks or months until the plant is accustomed to conditions inside your home. This will help prevent transplant shock and environmental stress that can cause the tree to drop all its leaves.
When you are ready to pot up, avoid using garden soil in the container. Garden soils are usually too dense for use in containers and can transfer weed seeds or pest and disease problems to your indoor garden.
Orange trees should be planted in soil that retains moisture but drains well enough to promote airflow and prevent rot. You can purchase a specialized citrus potting mix specially formulated to make the roots happy or amend high-quality potting soil with coconut coir and sand to create a well-draining, slightly gritty mix.
Temperature and Humidity
Orange trees thrive in warm tropical and subtropical climates. They don’t appreciate the cold at all and struggle to grow in temperatures below 50F. If they are left outside in temperatures below 40F, they may face damage that stunts growth, potentially killing off the tree if temperatures don’t improve.
That’s why keeping your orange tree indoors over the cool fall and winter months is vital. Even if you move the tree outdoors in summer to maximize sunlight exposure, it must be protected from nighttime temperature drops below 40F.
Air conditioners or radiators can also change conditions around the tree. It’s best to keep temperatures relatively consistent, moving the pot out of the path of air conditioners or open windows where they will be exposed to strong drafts.
Indoor orange trees will be happy in moderate humidity levels. Excessively high humidity can increase your disease risk, while dry air can lead to growing problems and blossom drop. If you need to increase humidity around the plant, use a humidifier, but don’t point the mist directly at the tree.
Fertilizing is essential to get the most out of your indoor orange trees. They use plenty of nutrients to grow lush leaves and produce fruits, quickly depleting what is in the soil in containers. Although they do grow slower than outdoor orange trees, it’s still essential to feed regularly due to the limited amount of soil.
Choose a fertilizer specifically formulated for citrus trees, applying around once every 1-2 months or according to packaging instructions. Each fertilizer type (liquid, granular, fertilizer sticks) will have different application requirements.
Pruning is a great way to manage the shape and improve the health of your indoor orange tree. Prune as necessary to shape the tree and remove any dead or diseased branches. Use clean and sharp pruning shears to make as clean a cut as possible.
As your indoor orange tree grows, repot to ensure it has enough room to continue thriving. Repotting is typically done every three to four years or slightly sooner for younger trees growing more rapidly. Look out for signs that the roots have no more room to expand, or wait until the soil is depleted before you consider repotting and refreshing the soil.
To repot your orange tree, start by selecting a pot one or two sizes larger than the current pot, depending on the tree’s age. Choose a pot with drainage holes to allow excess water to escape – pebbles at the bottom of the pot are not a replacement for adequate drainage.
Remove the tree from its current container and trim any dead or rotting roots with clean, sharp pruning shears. Place the tree in the new pot and fill in with the soil mix described previously. Keep the soil at the same level, as burying too deeply can damage the tree’s central trunk.
Water thoroughly after repotting and place it in the same sunny spot. Keep an eye on the tree during the weeks after repotting, as it may experience some transplant shock. You may notice signs of stress, such as yellowing leaves or wilting, but the tree should recover after a few weeks.
Propagating your indoor orange tree is not something I would typically recommend or do myself. You’ll see far more success purchasing a new plant to keep indoors than you would struggling with propagation. However, if you’re happy to try it as an experiment and are willing to wait several years to see fruit, here’s how to get it right.
Propagating From Seed
When growing from seed, the tree you get may not produce the same fruits as the one you collected the seed from, depending on the variety you’re growing. They also take several years to mature (with calamondins an exception, growing rapidly into lush trees in about two years). Many oranges are also seedless, eliminating this option altogether.
To propagate an orange tree from seed, start by extracting the seeds from a ripe orange. Lightly rinse the seeds under water to remove flesh and allow them to dry. Plant in a well-draining soil mix and cover with a thin layer of soil.
Place the container in a warm spot with bright indirect light and keep the soil moist but not wet. Be patient and watch the pot for signs of growth, transplanting when the young tree outgrows the container.
Propagating From Cuttings
Propagating orange trees from cuttings is a more reliable method than seed propagation. Start by trimming a 6-inch branch from a healthy, mature tree. The cutting should have at least two sets of leaves and no fruit.
Dip the end in rooting hormone to stimulate root growth (although this step is optional) and plant in a well-draining soil mix. Cover the container with a plastic bag to trap humidity and place in a warm, sunny spot. Keep the soil moist, and roots should develop within a few weeks.
Growing an indoor orange tree is not difficult, but since they are not accustomed to growing indoors, you may face a few of these common problems:
Yellowing leaves can be a sign of a problem with watering (usually underwatering, but also possibly overwatering) or a nutrient deficiency.
Overwatering can lead to root rot, so allowing the soil to dry out between waterings is essential. Underwatering can also stress the tree and cause the leaves to turn yellow. Be sure to water regularly, but adjust your watering schedule according to the size of the pot and the humidity levels in your home.
If the soil moisture is not an issue, consider fertilizing with a citrus fertilizer to tackle any nutrient deficiencies.
Leaf drop can occur due to sudden changes in temperature or humidity, as well as overwatering or underwatering.
Keep your tree in a consistent environment, avoiding drafts and sudden temperature changes. Adjust your watering schedule according to the size of the pot and the humidity levels in your home. If the problem persists, consider repotting the tree in fresh soil to refresh the root system.
Stunted growth is usually caused by poor soil quality or inadequate light.
Ensure that your tree is planted in well-draining soil and receives at least four hours of sunlight daily, preferably more. If your home doesn’t provide enough light, consider supplementing with grow lights to resolve the problem.
Lack Of Fruit
Lack of fruit is typically a problem with inadequate light but can also result from a nutrient deficiency or inconsistent watering.
Ensure your tree receives plenty of direct sunlight daily (closer to six hours for fruit production). If the tree is not receiving enough nutrients, fertilize with a citrus-specific fertilizer according to the package instructions. Watch your watering schedule to prevent any blossom drop and subsequent lack of fruit.
Remember that, like any other fruit, most citrus does require pollination. When your tree flowers, be sure to “be the bee” and transfer pollen between the flowers.
Common pests affecting indoor orange trees include scale and spider mites. These pests can cause deformed or discolored leaves and stress the tree, leading to other problems.
Look for signs of pests and treat with insecticidal soap or neem oil based on the pest’s species. Be sure to follow the instructions on the product label for the correct application.
Root rot, powdery mildew, and citrus canker are all possible problems with orange trees that you may find indoors, although less often than outdoors.
Root rot occurs due to overwatering, so allow the soil to dry out slightly between waterings. Both powdery mildew and citrus canker can be treated with targeted products for those issues. Also, keep your tree healthy year-round to make it less susceptible to pest and disease issues.
Frequently Asked Questions
Do indoor orange trees need to be pollinated?
Indoor orange trees can produce fruit without being pollinated by bees or other pollinators, but better pollination will increase yield. If your tree is not producing fruit, consider hand-pollinating the flowers with a small brush to transfer pollen yourself.
When should I bring my orange tree inside?
If you are growing your orange tree in a pot and moving it outside during the warmer months, bring it inside before the first frost. Orange trees are not frost-tolerant and can be damaged by cold temperatures.
Why is my indoor orange tree losing leaves?
Leaf drop can occur due to sudden changes in temperature or humidity, as well as overwatering or underwatering. Manage environmental conditions and adjust your watering schedule according to the size of the pot and the humidity levels in your home.
Growing an indoor orange tree is incredibly rewarding if you don’t have the space to grow citrus outdoors. Follow these basics to maximize growth and, by extension, your harvest.