How to Grow and Care for Orange Trees

Orange trees are one of the most recognized types of citrus trees featuring full, leafy canopies and sweet-smelling flowers followed by their famous fruit. A full-size orange tree can grow to 32 feet tall, with dwarf varieties reaching about 12 feet in height. Orange trees are planted in the ground after the possibility of frost has passed but dwarf trees can be planted any time in containers, which makes them perfect for growing indoors as a houseplant as well.

Although the fruit is delicious, the plant itself is known to be toxic to pets.

How to Plant Orange Trees

When to Plant

Orange trees can be planted at any time of year in warm climates, like southern Florida where they represent a major food crop. For cooler climates with significant seasonal variations, orange trees grow better when planted in spring or summer which allows them to acclimate before cooler weather arrives.

Selecting a Planting Site

Orange trees require plenty of sunshine and warmth, which are key factors for producing sweeter fruit. Choose a sunny site for an orange tree grown outdoors in USDA hardiness zones 9 to 11. Make sure the spot gets eight to 10 hours of sun daily. Orange trees are susceptible to wind damage so some protection is needed.

Spacing, Depth, and Support

Since these trees can grow fairly large, depending on variety, space them about 20 feet apart. For dwarf varieties, 10 feet should be sufficient. Orange trees are self-fertile and do not require another orange tree to produce fruits. However, including more than one orange tree in your garden will attract more pollinators which can increase fruit production.

Dig a hole about twice as large as the tree's root ball. Place the tree in the hole so the top of the root ball sits flush with the soil line. Support is typically unnecessary for orange trees, although dwarf orange trees may need staking when they begin fruiting.

Orange Tree Care

Light

Orange trees need lots of sunlight to grow the best-tasting fruits, so choose a spot that receives full sun for eight to 10 hours a day. For dwarf varieties grown indoors, place them in a sunny window.

Soil

Orange trees require loamy, rich, well-draining soil. Excess water must be able to drain away, as orange trees can't handle heavy, wet soil. At time of planting, mix in potting soil for additional nutrients. Slightly acidic to neutral soil pH levels from 6.0 to 7.0 work best.

Water

Orange trees need consistent watering but don't tolerate soggy soil. Drainage can be improved by building up a small mound at the bottom of the planting hole. Established orange trees should get about 1 inch of water per week. The amount of rainfall your area gets will impact whether or not you have to supplement with water from the hose.

Yellowing leaves on an orange tree may indicate root rot from overwatering.

Temperature and Humidity

Orange trees thrive in subtropical regions with warmer temperatures and moderate levels of humidity. Orange trees can grow outside in USDA hardiness zones 9 through 11. When temperatures slip below 50°F, the trees will begin to go dormant.

The optimal temperature to grow an orange tree hovers between 60°F and 90°F. This applies to trees in the ground and in pots. However, it does depend on the cold tolerance of the type of orange tree planted. For example, a naval orange tree is not as cold-hardy as a mandarin orange tree.

The fruit may split its skin during prolonged hot, humid periods. This may also happen when the tree quickly drinks up water after somewhat of a drought period, which can cause fast swelling of fruit and splitting of the skin.

Fertilizer

When grown in cooler areas, orange trees should be fertilized every month or two during its growing season. In warmer hardiness zones, such as 10 and 11, fertilizing year-round encourages continual growth and fruit production.

For young trees, start with a small amount of fertilizer, diluted to about half-strength. As the tree matures, switch it to full-strength fertilizer and distribute it around the tree, all the way out to the drip line. Use a balanced fertilizer, like a 10-10-10, or one specifically for citrus trees.If the veins of an orange tree's leaves are yellowing, it could be that the tree is not receiving enough nitrogen.

Types of Orange Trees

• Navel orange: Navel oranges are common varieties usually available in grocery stores. You can identify them by the navel-looking mark on the bottom of the fruit. Navel oranges are sweet, seedless, and great for juicing or eating as a snack.
• Blood orange: Known for their unique red coloring and sweet flavor, these oranges are a popular ingredient in prepared dishes and good for snacking.
• Valencia orange: Another common variety, Valencia oranges contain a high juice content ideal for juicing. They do have seeds.
• Satsuma orange: This small, sweet, and cold-hardy orange has fruits with loose, leathery skin, and is better known as the mandarin orange. The tree can take up to eight years to bear fruit.

Harvesting Orange Trees

Harvesting oranges is simple. It depends on the variety of tree you have to know when to pick an orange tree of its fruit. For example, navel oranges are ready to pick between November to June and Valencia oranges are ready to pick from March through October.

Once you determine when it's the best time to harvest your orange tree, look for fruit that is bright and consistent in color, firm with a slight give, and fragrant. Those are ripe and ready to pick and eat. Gently pull them from the branch, or use snips to cut the fruit from its stem. Just be sure it is ready, as oranges do not ripen after they are picked. Store oranges in the refrigerator. They should last a few weeks.

Pruning

Pruning following fruit harvest will benefit the following season's crop. In cooler growing zone regions, orange trees should be pruned in the fall after the fruiting but before the cold rolls in. But in regions where temperatures are consistently warm year-round, pruning can be done at almost any time, though it is most effective before new growth begins in spring.

Pruning for shape is not necessary; only do it if you want. Prune away any dead or damaged branches or branches that cross. This provides good airflow and light, helping to keep the tree healthy. Young trees should have branches removed that are less than a foot above the ground.

Propagating Orange Trees

Orange trees should be propagated via cuttings. The best time to do it is late spring or early summer when there is new growth.

To propagate orange trees, you need sharp snips, a pot, rich and well-draining soil, rooting hormone, and a plastic bag.

1. Identify and cut a branch. Choose a 6-inch branch tip with healthy leaves. Make a 45-degree cut below a leaf node.
2. Prep the cutting for planting. Remove any blossoms or growing fruit and the leaves on the lower half of the cutting. Use a clean knife to score the bark at the end of the cutting. Dip the cut end in rooting hormone.
3. Prep the pot. Fill the pot with soil and moisten it. Then poke a hole in the center for the plant cutting.
4. Plant the cutting. Place the cut end of the cutting in the hole. Firmly tamp down the soil around it. If the soil can't hold the cutting upright, you can moisten it a little more.
5. Cover and place correctly. Cover the pot with a plastic bag to keep humidity levels up. Set the pot in a warm spot that gets bright, indirect light.
6. Daily care. Open the bag at the bottom every day to allow some air circulation. Check the soil moisture and add water if you need to to keep it moist.
7. Remove the bag. After a week or so, remove the bag and let the cutting adjust to regular humidity levels. Continue to moisten the soil regularly.
8. Longterm care. After the roots form, place the cutting outdoors in a partially shaded area that's protected from wind. After several months, slowly expose the cutting to more sun until it's ready to be planted in direct sun.
   

How to Grow Orange Trees From Seed

It is possible to grow orange trees from seed, though the seed may not produce a tree with the same characteristics. To grow orange trees from seed you'll need a bowl of water, a tray or small pot with rich potting soil, and a plastic bag.

1. Soak the seeds. Soak the seeds in a bowl of water for 24 hours. Any seeds that float should be thrown out.
2. Plant the seeds. Take the soaked seeds that did not float and plant them 1 inch deep in moist soil.
3. Keep warm and moist. Set the pots in a warm spot and keep soil moist. Put a plastic bag over the pot to help keep humidity levels high. Adjust the bag every day to allow for air circulation and keep the soil moist.
4. Remove the bag. Once the seeds have germinated, remove the plastic bag.
5. Place in bright light. Take the seedlings and put them in a spot that gets bright light. Add a grow light if necessary.
6. Repot seedlings. Repot each seedling into its own container and continue to give bright light.

Potting and Repotting Orange Trees

Dwarf orange trees are popular fruit trees to keep in pots. This is a great option if you live in climates colder than those recommended for growing citrus. A potted tree can be brought indoors before cold temperatures hit.Choose a deep pot made from wood, clay, or even plastic but make sure it has plenty of good drainage holes to accommodate the root system.

Orange trees should be repotted about every two to four years, depending on the kind of tree you have. Stunted growth or roots coming out of drainage holes are the two most common signs the tree has outgrown its pot. The ideal time to repot is spring, before new growth arrives.

To repot an orange tree, tip the container to its side. Tap or squeeze the outside of the pot to loosen the root system, then hold onto the base of the trunk near the soil and gently slide the tree out. Add an inch or two of soil to a new container that's several inches larger than the old container. Place the tree inside, then fill in with new, rich soil. Tamp the soil down and water.

Overwintering

When grown in the appropriate growing zone, orange trees shouldn't need much for overwintering. Remove any leftover fruit and water the tree less. In zones with a threat of frost, insulate the tree with frost cloth.

For orange trees grown outside of their ideal growing zone, you must move the tree indoors in advance of heavy frost.

Common Pests and Plant Diseases

Like many fruit-bearing plants, orange trees are prone to specific pests and diseases. Pests that commonly attack orange trees include aphids, scale, spider mites, Asian citrus psyllids, and leafminers.

Different fungal and bacterial diseases can affect the trunk, leaves, and fruit. Small blistering spots that are brown, brown with yellow halos, or cause holes on leaves typically mean your tree has citrus canker. Use copper fungicides to combat the problem.

Yellowing leaves may indicate that the tree is affected by citrus greening. This is a bacteria transmitted by the citrus psyllid. There's no cure for citrus greening, but you can control psyllids with neem oil or other insecticidal soaps.

From: thespruce