Navel Orange Tree Care: Sweet Orange Fruit
How do you grow a navel orange tree? We'll explain the process and reveal what you need to know to get great harvests year after year!
Navel oranges have become severely underrated as the popularity of mandarins has skyrocketed. Growing a navel orange tree will provide delicious, sweet fruit during the winter when most gardens slow down or go completely dormant. A navel orange tree can be grown as a dwarf or standard tree in the ground or a container making it feasible for just about any gardener to grow. They can be grown as a patio tree in almost any growing zone as long as they can be brought inside during harsh winters.
Navel oranges are naturally seedless and perfectly sweet. They are incredibly versatile as they can be used in an infinite number of recipes, homemade cleaners, and even for DIY home décor. Navel oranges are also remarkably nutritious and healthy. Oranges are packed with vitamin C, potassium, and fiber which provides several health benefits such as preventing heart disease, cancer, and stroke.
Although navel oranges are easily found in stores, there’s nothing more convenient than growing them in your own yard. The amount of produce that one tree can provide is more than enough to share and may encourage you to get creative and try some new recipes.
Good Products At Amazon For Growing Navel Orange Trees:
- Safer Brand Insect Killing Soap
- All Seasons Horticultural And Dormant Spray Oil
- MycoStop Biofungicide
- Southern Ag Liquid Copper Fungicide
Quick Care Guide
|Common Name(s)||Orange, navel, navel orange, sweet orange|
|Scientific Name||Citrus sinensis|
|Days to Harvest||Annually in the winter or spring|
|Soil||Well-draining sandy loam soil|
|Pests||Mites, thrips, scales, aphids, lepidopterans, Asian citrus psyllid|
|Diseases||Phytophthora root rot, Anthracnose, Botrytis, Huanglongbing (HLB)|
All About The Navel Orange Tree
Sweet oranges are classified under the botanical name Citrus sinensis which is a cross between a pummelo and a mandarin. Sweet oranges include navels, valencias, and blood oranges.
Navels are different from other types of sweet oranges because they are seedless. A mutation on sweet orange caused a small secondary fruit to form on the flower end of the fruit, creating that “belly button” appearance. This secondary fruit is also the reason why navel oranges are seedless. The original mutation was found in the 1800s in Brazil and eventually brought to the United States as the Washington navel orange. Additional mutations to Washington navel orange have been discovered and developed into new navel varieties.
Citrus sinensis is an evergreen tree that ranges in size from 6-30 feet depending on the variety and rootstock. Trees bloom in the spring, the fruit develops in the summer and fall, and it is ready to harvest in the winter or spring. Navel orange trees have dark green, elliptical, waxy leaves. The blooms are white and fragrant. The fruits are green during development and turn a bright orange color when ripe. The average fruit size is around 3 inches in diameter. Navel oranges are self-fertile, so they do not require pollination.
Although there are several navel varieties, there are a few worth highlighting. Even though the Washington navel orange is an old variety, it is still one of the best varieties to grow today. It’s ready to harvest between November and January. If you have ever eaten navel oranges from the store, they were most likely Washington navel oranges.
Cara Cara is another variety that is also ready to harvest between November and January. Cara Cara is a result of a mutation on a Washington navel orange tree. It has an excellent flavor, and the flesh is deep pink instead of orange.
Lane Late is a late-maturing mutated bud sport from a Washington navel orange tree. This variety is very similar to the Washington navel orange but it is ready to harvest between February and June. The fruit stores extremely well on the tree extending the harvesting season for a few months.
The best time to plant navel orange trees is from April through August. Avoid planting when temperatures are above 100°F. Plant in a sunny location in well-draining soil. If the soil has poor drainage, plant in a raised bed or a large container, like the 10-gallon Air Pot we stock in our store.
Since navel oranges are seedless, they must be planted as a grafted tree. Dig a hole twice as wide as the root ball and fill in with loose soil. When you plant, do not bury the graft union and try to leave at least a few inches of the rootstock above the soil. If planting in a container, navel orange trees will need at least a 15-20 gallon container. Young trees can be planted in a smaller container and later transplanted as the tree grows and matures.
Trees should be purchased from a trusted nursery or garden center that follows local regulations in regards to citrus. Citrus-producing states such as California, Texas, Arizona, and Florida may have movement restrictions on young trees. Check with your local Agricultural Extension Office for more information on restrictions in your area.
Navel orange trees are known to grow with minimal effort. Applying all the care tips below will result in high-quality produce and a beautiful tree.
Sun and Temperature
Navel orange trees require full or partial sun meaning it needs at least 8 hours of direct sun each day. Hot summers and mild winters yield the best quality fruit. They are hardy to USDA zones 8-11, so they can tolerate temperatures down to 20°F for a short period and temperatures above 100°F. Temperatures below 26°F may damage the produce.
Navel orange trees can be grown as containerized patio trees in USDA growing zones 4-11 as long as they can be brought indoors when temperatures drop below freezing. You may also be able to provide some alternative method of keeping the tree warm during the winter if you’re in a cooler growing zone. Trees can be protected from frost by bringing indoors or by covering with frost fabric.
Sunburn is common on excessively hot summer days, especially on tender growth, but the damage is minimal and the trees will eventually grow out of it. Sunburn can be prevented by covering trees with light shade cloth or by covering the tree with a whitewash.
Water and Humidity
Water citrus early in the morning once a week. Soil should be kept moist, but not soggy or saturated. Use soaker hoses or drip irrigation to avoid wetting the trunk of the tree. Trees should be well watered during fruit development. Irrigation frequency and/or amounts should be reduced during the cooler wet months to prevent overwatering.
Trees planted in a pot may need to be watered more often. They should be fully saturated and allowed to dry down until slightly moist before the next watering. Potted trees can be watered using drip irrigation or manually with a hose. If watering manually, avoid wetting the trunk.
Navel oranges grow best in well-drained, sandy loam soils with a pH between 6.0-7.0. If planting in heavy clay soil, amend with organic matter.
There are a lot of different citrus tree fertilizers available at garden centers. The rates and application frequency depend on the fertilizer blend and whether it is a slow-release fertilizer. Slow-release blends typically need to be applied once or twice a year. Navel orange fruit trees should be well fed from March-August when trees are most actively growing.
Navel oranges can be pruned at any time of the year but the ideal time to prune is in the late winter or early spring before bloom. Navel orange trees are not deciduous so their leaves will remain throughout the entire year. They do not require older growth to produce fruit. Flower buds are very noticeable on trees. Pruning off flower buds will reduce the number of oranges for the season.
Suckers and dead or damaged wood should be removed annually. Suckers are shoots that grow from the rootstock. These shoots will look different from the fruiting variety and should always be removed. These shoots will not produce good fruit. Remove suckers by cutting them flush with the main trunk. When removing deadwood or diseased branches, prune back several inches below the dead or diseased branch to ensure the entire infection or dead portion is removed. Old or damaged fruit should also be manually removed. While it should fall off naturally, removing old fruit will prevent diseases. It also preserves resources for shoot development and flowering.
Trees can be trained and pruned as a hedge, espalier, or standard tree. Standard trees should be pruned to keep the center open to optimize sunlight and airflow throughout the canopy. Trees can reach a mature height of up to 30 feet. Pruning is an excellent way to maintain the desired shape and height of your navel orange tree.
Before propagating citrus, check for local restrictions on citrus propagation. In some areas like California, Arizona, Texas, and Florida, it is illegal to propagate citrus material that does not derive from a clean stock program.
Grafting is the most reliable way to grow a strong disease-resistant navel orange tree. Navel oranges are commonly grafted onto C-35, Carrizo, or Trifoliate rootstock. Rootstocks are grown from seed but can be bought as liners. Once the rootstock is thick enough, it can be grafted with the desired variety. Chip budding is the most common method used for grafting.
Harvesting and Storing
Harvesting navels is super easy and can be done as needed. Navels store extremely well on the tree but there are also some great options for storage post-harvest.
Navels are typically ready to harvest in the late winter or early spring. The cold temperatures during the winter trigger the color change from green to orange. The best way to test for readiness is by tasting the fruit. After harvest, navels will not sweeten so it’s important to pick the fruit when it has developed enough sugars.
Do not pull navel oranges off the tree. Pulling the fruit can cause damage to the limbs of the tree. The best way to harvest is to twist up at an angle or cut the fruit off the tree with clippers. Harvesting does not need to occur all at once. Navels can remain on the tree for an extended period before quality declines. Oranges should be washed before storing to prevent any contamination.
Navel oranges will store for up to a week at room temperature and up to 4 weeks in the refrigerator.
Freezing is an easy and excellent option for long-term storage. There are a few different ways to freeze depending on what part of the orange you plan to use. Juice can be frozen and stored for 3-4 months. Orange zest can be stored for up to 1 year. When storing the fleshy part of the fruit, remove the peel, segment it into slices, and store it in a freezer bag or container for up to 1 year.
Navel oranges can also be canned, used to make marmalade, or dehydrated, extending the storage life to up to 1 year.
Navel orange trees rarely have growing problems once they are fully grown and established. Below are some common issues that you may encounter as your tree grows and matures.
Excessive stress from heat or lack of water may cause flowers to abort or early fruit drop. Although some fruit drop is normal, too much indicates stress. Differences in weather such as heavy rain or a warm winter will cause variations in fruit quality. Some years will yield better fruit than others due to natural temperature and rain fluctuations.
Micronutrient deficiencies, especially zinc and iron, are common with navel orange trees. The most common sign of deficiency is yellowing between the leaf veins. If trees are showing signs of micronutrient deficiency, check the fertilizer used to make sure it includes all the essential micronutrients. If it does, check the soil pH before applying more fertilizer. High soil pH can inhibit some micronutrient availability. Acidifying fertilizers can be used to lower pH to an optimal level.
Mites are small arachnids that feed on the leaves of orange trees. There are several species of mites that feed on citrus. The most common mites cause stippling damage on the leaves. Heavy infestations will cause leaf drop. Mites tend to attack weak or stressed trees. Keeping a healthy navel orange tree is the first line of defense against mites. If mite populations get out of control, use horticultural oils and insecticidal soaps to knock down heavy infestations.
Citrus thrips are small yellow to orange insects that feed on flower blooms and young tender leaves. Feeding damage causes curling and scarring on the leaves and scarring on young fruit. Citrus thrips feed on tender new foliage, so damage does not significantly impact mature plants. Feeding damage can stunt the growth rate on young trees with an abundance of tender new flushes. Thrips are very difficult to control by spraying, so it is not recommended. On younger trees, a good option is to protect the tree with insect screens until the new leaves are no longer tender and attractive to thrips.
Soft and armored scales can be found on the twigs and branches of trees. Damage usually does not come directly from the scale. Scales excrete excessive amounts of honeydew which leads to sooty mold. Sooty mold covers the leaves which inhibits photosynthesis and leads to leaf drop. Scales are usually controlled by natural predators and parasites. If treatment is necessary, weekly oil sprays are effective.
Aphids are small soft-bodied insects that feed on the sap of tender plant tissue. They can cause some deformation in leaves. These also produce honeydew which can lead to problems like sooty mold. Aphids are usually controlled by natural predators; however, populations can still become off-balance and damaging. Control by manually removing leaves with heavy infestations and by hosing them off the rest of the foliage with water. Horticultural oils and insecticidal soaps are also effective.
Lepidopteran pests include several types of moth larvae that cause damage to the leaves. There are a few leaf roller species that cause damage to the tender growing tips. Citrus leaf miner is also a lepidopteran pest that mines tunnels on the undersides of leaves. Lepidopteran pest damage is mostly cosmetic but can stunt growth in young trees. Treatment should not be necessary on mature trees, and larvae can be manually removed on young trees. Pheromone traps can be placed on trees to disrupt mating, effectively reducing the population.
Asian citrus psyllid is a small mottled brown insect around the same size as an aphid. Psyllids inject a toxin during feeding which may cause a burn back on tender new growth. However, feeding damage is not the main concern. They are considered a major pest because it vectors a devastating disease called Huanglongbing (HLB) or citrus greening disease. Depending on your area, the presence of Asian citrus psyllid will warrant different responses. Research the local regulations and reach out to your county office if there are any questions.
Phytophthora root rot is one of the most common root diseases in citrus trees. The most common symptoms are a general decline in health and the leaves will turn yellow or pale green. Advanced stages will present “gumming” or sap oozing from the trunk of the tree. Trunks may also exhibit a water-soaked appearance. Phytophthora is prevented by using best irrigation practices and planting in well-draining soil. Most rootstocks have some form of resistance or tolerance to the disease. Still, it is extremely important to leave at least a few inches of the rootstock above the soil line. Most fruiting varieties are very susceptible to phytophthora, so leaving the graft close to the soil increases the risk of infection. There are beneficial microbes and mycorrhizae products that can be applied to boost plant health and immunity to diseases like phytophthora. However, good watering practices will be enough for prevention.
Anthracnose and Botrytis are both foliar diseases that thrive in wet conditions. Symptoms of these two diseases are twig dieback, leaf drop, and fruit decay. Anthracnose is identified by the dark spores on the leaves and twigs while botrytis spores are a lighter gray color. Both diseases can be managed with good cultural practices. Prune trees to allow adequate airflow to avoid excessive moisture that favors spore development. Removing dead or damaged branches and old fruit will prevent the disease from infecting the following season. Infection is usually mild, so fungicide treatments are rarely needed.
Huanglongbing (HLB) is also referred to as the citrus greening disease. This incurable disease is devastating to the navel orange tree. Citrus with this disease may have yellow mottled leaves, sudden death in young trees, small or deformed fruit, and discolored or green fruit. This disease is spread by the Asian citrus psyllid. Controlling the insect prevents the disease. It can also be transferred when grafting with infected plant material. Once a navel orange tree is infected, it needs to be removed. Ensure that any new trees planted come from reliable nursery sources that are following state regulations. For example, citrus trees grown in California should have a CDFA label that shows they have come from clean nursery stock.
Frequently Asked Questions
Q: How long does it take a navel orange tree to produce fruit?
A: Navel orange trees take about 4 years to produce a substantial amount of fruit. They will yield small amounts of fruit as early as 2 years.
Q: How big does a navel orange tree get?
A: Tree size depends on the variety and rootstock combination. A dwarf tree will grow between 6-8 feet tall, a semi-dwarf tree will grow between 10-15 feet tall, and a standard tree can grow up to 30 feet tall.
Q: Are navel orange trees self-pollinating?
A: Yes, navel orange trees are self-pollinating.