Tree · Rutaceae
Orange
Citrus × sinensis
Give it full sun, warmth, and well-drained soil, and a sweet orange tree will thank you with fruit for decades.
Full sun
Every 7–14 days
55–100°F · 13–38°C
USDA 9–11
Overview
The sweet orange has become the most widely grown citrus anywhere, and it is a friendly tree to get to know: evergreen, with glossy leaves, sweet-smelling white blossom, and fruit that colors up through the cooler months. It sits in the rue family beside lemons and limes, and it feels most at home where winters stay gentle, roughly USDA zones 9 to 11. If frost is a concern where you are, don't let that stop you, because a large pot lets you bring the tree indoors for the winter.
Think of an orange tree as a long-term companion rather than a quick project. It grows at a moderate pace and can climb to 20 to 30 feet (6 to 9 m) in the ground, then live and fruit for decades once it feels settled. It blooms in spring and ripens its fruit slowly through fall and winter, so on the same branch you will often find blossom and ripening oranges keeping each other company.
Nearly every orange you meet started life as a graft, with a chosen variety joined to a hardy rootstock that shrugs off cold and disease. That is simply why a seed from your breakfast won't grow the same fruit, and it is nothing you did wrong. Choose a variety suited to your climate, offer it sun and steady water, and you can trust the tree to carry the rest.
Care
The short version: full sun, warmth, and well-drained soil, watered deeply but not too often, with a balanced citrus feed through the growing season, and the rest will fall into place.
Light
An orange loves full sun, ideally 8 or more hours a day, which is what sweetens the fruit. It will forgive a bit of afternoon shade, so don't fret over a less-than-perfect spot, but the more sun it soaks up, the fuller and sweeter your crop will be.
Water
Water deeply but not often, letting the top half of the soil dry out between drinks, which usually works out to every 7 to 14 days. Young trees and those in pots want a little more, while a tree settled in the ground copes well with a dry spell. The one thing an orange truly won't forgive is soggy, waterlogged soil.
Soil
Give it well-drained sandy loam so water never lingers around the roots. A pH between 6.0 and 7.5 keeps the tree happy, and honestly, good drainage matters far more than getting the exact soil type just right.
Temperature
Oranges are comfortable from about 55°F to 100°F (13°C to 38°C) and want a frost-free home. A hard freeze can hurt the wood and fruit, so if your tree lives near the edge of its range, a pot you can wheel indoors for the cold is a kind bit of insurance.
Humidity
Average humidity of 50% to 70% keeps an orange content, and most warm regions supply that on their own without any fuss. A tree brought inside for winter will welcome a little extra moisture in dry, heated rooms.
Feeding
Feed with a balanced citrus fertilizer that includes micronutrients like iron, zinc, and manganese. Spread it through the growing season, from spring into late summer, then ease off as the weather cools, and your tree will keep pace nicely.
Pruning
Happily, oranges ask for little pruning. Take out any dead, damaged, or crossing wood and snap off suckers that pop up below the graft, doing this in late winter or early spring before the new flush arrives.
Repotting
A tree in a container appreciates a fresh, larger pot every 2 to 3 years. When you notice roots circling the pot, water running straight through, or growth slowing with yellow leaves, that is your tree's gentle way of asking for more room.
Size & spacing
A standard orange tree reaches 20 to 30 feet (6 to 9 m) tall and spreads 12 to 20 feet (3.6 to 6 m) wide, so give it open room away from buildings and other trees and it will settle in beautifully.
When to plant
An orange tree loves warmth and simply cannot weather a hard frost, so let the weather set your pace. Plant a new tree in spring once the last freeze is behind you, and it will bloom the following spring, with fruit ripening from fall through winter and into spring depending on the variety you chose.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: Spring after all danger of frost has passed
- Harvest: Blooms in spring; fruit ripens fall through winter and into spring depending on cultivar
Hardiness
USDA hardiness zones: 9–11
Temperature: down to -7°C
Troubleshooting
Most orange tree troubles show up first on the fresh leaves and the fruit, which is actually good news, since it gives you an early warning. A couple of these are simply insects you can handle, while two are serious diseases worth spotting soon. Find what matches below, then step in gently before it spreads through the rest of the tree.
Yellow-blotched leaves paired with small, lopsided fruit
Take a breath, because this one is out of your hands: patchy yellowing with lopsided, bitter fruit points to citrus greening, also called huanglongbing, and it is the hardest blow a citrus tree can take. A little insect known as the Asian citrus psyllid carries the bacterium between trees, and no treatment will bring an infected tree back. The kindest thing you can do for the trees around you is to remove and destroy yours and let your local agricultural office know.
Fix:
- There is no cure; remove and destroy infected trees to reduce spread
- Control Asian citrus psyllid populations
- Report suspected cases to local agricultural authorities
Corky tan spots rimmed with yellow on fruit and leaves
Raised, scabby spots ringed in yellow are the sign of citrus canker, a bacterial disease that travels on wind-blown rain and on wet hands. Don't panic; clip away and destroy the affected wood and fruit, and use a copper spray if your area allows it. Since many places treat canker as reportable, check your local quarantine rules before moving any part of the tree, and you will be on the right side of things.
Fix:
- Remove and destroy affected plant material
- Apply copper-based sprays where permitted
- Follow local quarantine and reporting requirements
Sticky leaves, sooty black film, and little bumps on the stems
The bumps that stay put when you rub them are scale insects, and the sticky sheen and black soot beneath them is simply the honeydew they drip. This is very fixable: coat them with horticultural oil and trim off any twig that has crusted over. It helps to watch for ants as well, since they tend the scale and chase off the helpful bugs that would keep it under control for you.
Fix:
- Apply horticultural oil to smother scale
- Prune heavily infested twigs
- Conserve natural predators and parasites
Silvery winding trails through curled new leaves
Those wandering silver squiggles look worse than they are, so try not to worry. They come from the citrus leafminer, whose larvae feed inside the tender new leaves and leave those tracks behind. A grown tree simply outgrows the damage, so you can leave it alone, and on a younger tree you can ease back on the soft growth that tempts the moth and reach for horticultural oil if the mining gets heavy.
Fix:
- Tolerate light damage on mature trees, which usually outgrow it
- Avoid excess nitrogen and pruning that stimulate frequent tender flush
- Use horticultural oil on young trees if needed
Toxicity
For people, an orange is a safe and healthy food, but for animals the story is a little different, and it helps to know why. The peel, leaves, and seeds carry essential oils and psoralens that upset a pet's stomach and can leave the skin touchy in sunlight. Keep peels and prunings out of reach of cats, dogs, horses, and other animals, and share only a little flesh as a rare treat.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds
Safe for
People
Cats Mild
The essential oils tucked in the peel and leaves usually leave a cat drooling, then vomiting, with a spell of diarrhea to follow. One that eats a good amount may go quiet and sluggish, and the psoralens can make its skin sensitive out in the sun.
Dogs Mild
A dog that gnaws on the peel or leaves will most likely get a sour stomach with vomiting and loose stools. A larger mouthful can leave it low on energy, so gently point it back toward its own treats instead.
Horses Mild
The oils and psoralens in the leaves and rind can unsettle a horse's belly and take the shine off its mood. Keep prunings and peels out of the paddock so a curious horse doesn't nibble on them.
Rabbits Mild
For a rabbit's gentle digestion the essential oils in citrus leaves and peel are simply too much and can leave it off its food with soft stools. The most a rabbit should ever have is a tiny scrap of flesh once in a while.
Livestock Mild
Goats, sheep, and cattle sometimes nibble at fallen leaves or peel, which can bring on mild stomach upset. Sweep up citrus trimmings from grazing areas so the animals aren't tempted to load up on them.
Birds Caution
The oils that gather in the peel and leaves are best kept well away from pet birds, though a small taste of the flesh is generally fine. Offer just a little seedless flesh and leave the rind out of it.
People Flesh safe
The juicy flesh is a wholesome, everyday food with nothing to fear. Just keep the peel, leaves, and seeds out of the bowl, since their oils can sting the mouth and stomach.
Keep peels, leaves, and seeds away from pets; the fruit flesh in small amounts is likely to cause at most minor stomach upset.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
Poison Control: (800) 222-1222
Canada
Poison Centres: 1-844-764-7669
Varieties
There are hundreds of orange varieties, sorted mostly into the ones you eat fresh and the ones you juice. The handful here are the ones you are most likely to grow yourself or recognize at the store.
Valencia
A late-season favorite for juice, harvested from spring into summer and loved for its almost seedless fruit and wonderful juice.
Washington Navel
The seedless eating orange you can spot by the tiny second fruit, the navel, that forms at its blossom end.
Hamlin
An early, cold-tolerant juice orange planted throughout Florida's groves.
Blood orange (Moro)
Its flesh deepens to a rich red once cool nights draw out the anthocyanin pigment.
How to propagate
Oranges are nearly always grafted so you can count on the fruit and a sturdy root, though you are welcome to grow one from seed if you have a few years to spare.
GraftingModerate
During active growth in spring to early summer when bark slips easily · Several months to form a union; 3 to 5 years to begin fruiting
Grafting is the usual and dependable way to raise an orange, whether in a big grove or a backyard, so you are in good company choosing it. Work in spring or early summer while the bark slips away easily, and the union will knit together over a few months. You get fruit that matches the parent along with the cold and disease tolerance of the rootstock, and all that is asked of you is patience, since the young tree needs 3 to 5 years before it starts to bear.
SeedEasy
Sow fresh seed in spring · Germinates in a few weeks but can take many years to fruit
Starting an orange from seed is one of the easiest things you can try, as long as you are happy to wait. Tuck a fresh seed into soil in spring and a sprout appears within a few weeks, though the tree may take many years to fruit and often won't come true to the parent. That is why seed is mostly a way to grow rootstock or simply to enjoy the experiment.
Myths
Oranges are completely safe for cats and dogs because the fruit is edible for people.
It is an easy thing to assume, but the ASPCA lists orange as toxic to cats and dogs, because the peel, leaves, and seeds hold essential oils and psoralens that upset the stomach. The juicy flesh is much gentler, though even that is best given as no more than a small, occasional treat for a pet.
A seed from a store-bought orange grows a tree just like its parent that fruits in a year or two.
It sounds lovely, but sweet oranges are nearly always grafted onto a rootstock rather than raised from seed. A seedling can take many years to fruit and often won't resemble the parent, which is why seed-grown trees are mostly kept for rootstock or for the fun of it.