Tree · Rutaceae
Blood Orange
Citrus × sinensis
Give it full sun and cold winter nights, and the blood orange brings home fruit the color of garnet.
Full sun
Every 7–14 days
USDA 9–11
8–30 ft · 2.4–9.1 m
Overview
Few trees earn their place in a sunny corner of the home quite like the blood orange, a sweet orange that keeps its drama on the inside. Slice one for the table and the flesh runs from streaked orange to deep garnet, a color set by anthocyanins, the pigments behind a bowl of berries. As an evergreen citrus it offers a fragrant spring and a winter laden with fruit, an easy anchor for a courtyard, a terrace, or a bright kitchen doorway.
Part of its appeal is how the color arrives. The flesh only deepens to red when warm days hand off to cold winter nights, so a tree set in a mild, even spot gives paler fruit. That same logic explains the romance of Sicilian groves, where the chill off Mount Etna lends the harvest its depth, and it is the kind of provenance that makes a single tree feel like a small piece of the Mediterranean at home.
Living with one asks little. It wants full sun, free-draining soil, and shelter from hard frost, and it suits a relaxed routine far better than a fussy one. A grafted tree settles over a few years, then quietly becomes part of the household, fruiting for decades and earning its keep as both a centerpiece and a pantry.
Care
The short version: a sunny, well-drained spot, with watering that stays steady yet measured so the roots never sit waterlogged. Feed through the growing season, shelter the tree from frost, and let cold winter nights bring the fruit to its garnet best.
Light
Give a blood orange full sun, and the more it bathes in it the better, since light drives both the crop and the sugar in the fruit. A little partial shade is tolerable, but a shaded tree flowers less and sets fewer oranges, so the brightest corner of the garden is the one to offer it.
Water
Soak a young tree about twice a week for the first month while it finds its feet, then ease back as the roots reach out. An established tree mainly wants water through dry spells, and the single thing to avoid is waterlogging, which citrus roots cannot abide.
Soil
Plant it in well-drained loam, silt, or sandy soil where water moves on rather than pooling. A slightly acidic pH of 5.5 to 6.5 suits the tree, though sharp drainage does more for it than chasing the exact figure.
Temperature
The tree lives comfortably across a wide range, from about 41°F to 100°F (5°C to 38°C), though a hard freeze will mark the leaves and twigs. Cold nights, however, are a welcome guest at fruiting time, since they are what turn the flesh red.
Humidity
Ordinary humidity of 40% to 60% keeps the tree at ease, so most climates within its range pose no concern. Good air moving through the branches matters more than meeting any precise number.
Feeding
Offer a balanced citrus fertilizer such as 8-8-8 with micronutrients across the growing season, roughly February to October. Spreading the feedings through spring and into fall keeps growth even and unhurried, which is just what a settled tree wants.
Pruning
A blood orange asks for very little pruning. Take out dead, damaged, or crossing branches and clear any suckers below the graft union, and do the work after the fruit ripens, since the flowers form on new wood.
Repotting
A tree in a container wants a roomier pot every 2 to 3 years. Roots circling the inside, roots slipping out the drainage holes, or growth that has quietly stalled all signal that the time has come to size up.
Size & spacing
Set in open ground a blood orange can rise 8 to 30 feet (2.4 to 9 m) tall with a canopy spreading 8 to 15 feet (2.4 to 4.5 m) wide. Give it that generous footprint so the branches drink in full sun and air drifts freely through the tree, and let it stand as a feature in its own right.
When to plant
The blood orange keeps a graceful winter rhythm. Set young trees out in spring once frost has passed, enjoy the fragrant white bloom that follows, and gather the harvest from winter into early spring, after a run of cold nights has brought the flesh to color.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: Spring, after danger of frost has passed
- Harvest: Fragrant white flowers in spring; blood oranges ripen winter to early spring (about December to April), developing deepest flesh color after cool nights
Hardiness
USDA hardiness zones: 9–11
Temperature: down to -7°C
Troubleshooting
Most trouble with a blood orange traces to insects, cold, or a single serious disease, and an early eye gives you the chance to save the tree or at least slow the loss. Read the signs below against what the tree is showing, then step in before the problem takes hold.
Mottled yellow leaves and uneven, bitter fruit
When the canopy loses its even green and the fruit comes in lopsided and bitter, the cause is citrus greening, the disease also named Huanglongbing and the most serious one a citrus can face. The Asian citrus psyllid, a small insect, carries it from tree to tree, and no remedy exists once a tree is infected. The graceful answer is to remove and destroy the affected tree, start again with certified disease-free stock, and keep the psyllid at bay long before it reaches the garden.
Fix:
- Remove and destroy infected trees
- Control the Asian citrus psyllid vector
- Plant certified disease-free stock
Falling leaves and spent twig tips after the cold
Leaves that fall and twig tips that wither after a cold spell point to freeze damage. A hard frost leaves the foliage water-soaked, then brown, and the leaves let go while the tips die back. Shelter the tree through a freeze, give it the warmest corner of the garden, and resist pruning until spring growth returns, since those bare twigs so often flush again once the season turns mild.
Fix:
- Provide cold protection during freezes
- Prune out dead wood only after new growth resumes in spring
A dark sooty cast over leaves and fruit
A dark, dusty cast over the foliage is sooty mold, a fungus that settles on the sticky honeydew dropped by aphids, whiteflies, scale, or mealybugs. It barely touches the tree and lifts away with a cloth, yet it quietly announces that sap-feeders are at work above. Treat those insects with horticultural oil and rinse the leaves, and with its food source gone the mold simply disappears.
Fix:
- Control the honeydew-producing insects with horticultural oil
- Rinse foliage to remove mold
Toxicity
The flesh is a pleasure at the table, but the rest of the tree is no place for animals. Peel, leaves, and seeds carry essential oils and psoralens that upset a pet's stomach and can irritate skin. In a home with animals, keep cats, dogs, horses, and grazing stock clear of the rind, foliage, and prunings.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds
Safe for
People
Cats Mild
A cat drawn to the peel or leaves may drool, vomit, or pass loose stools and seem subdued for a while. The oils in the rind can leave the skin reddened and itchy as well, so keep curious pets clear of the fruit bowl.
Dogs Mild
Expect an upset stomach, vomiting, or diarrhea from a dog that helps itself to the rind or foliage, and the oils can irritate the skin on contact. A tidy kitchen and a high shelf spare everyone the trouble.
Horses Mild
The ASPCA lists sweet orange as toxic to horses, the same peel oils and psoralens unsettling the gut. Keep prunings and windfall peels well away from the paddock when the tree grows nearby.
Rabbits Caution
The peel and leaves hold those same irritating oils, so they make a poor treat for a rabbit. A small piece of the flesh on occasion is fine, but the rind and foliage are best skipped.
Livestock Caution
Goats, sheep, and cattle can take a little pulp, but a fill of bitter peel and leaves brings on digestive trouble. Keep them from browsing the tree or the trimmings left after a tidy-up.
Birds Caution
A morsel of the juicy flesh is a treat many birds enjoy, while the oily peel and pith are better left off the menu entirely.
People Flesh safe
The juicy flesh is a kitchen favorite and entirely safe to eat. Working with a lot of peel can leave sensitive skin tingling in sunlight, owing to the psoralens in the oil, so a quick rinse after zesting is wise.
The fleshy fruit pulp is edible, but keep peels, leaves, seeds, and concentrated peel oils away from pets.
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
Three blood orange cultivars come up again and again, each offering its own balance of color, sweetness, and season. These are the names worth knowing when you choose a tree for the home.
Moro
Moro brings the deepest and most dependable crimson-to-burgundy flesh of the three, with the highest anthocyanin content and a berry note that recalls raspberry on the palate.
Tarocco
Tarocco, Italy's most widely grown blood orange, is sweet and low in acid with almost no seeds and flesh that shades from orange to red.
Sanguinello
Sanguinello, a late-season Spanish cultivar, carries few seeds and a moderate red color, and it keeps its quality on the tree long after ripening.
How to propagate
Blood oranges reach the garden almost entirely by grafting, the method that copies a favored tree exactly. Seed is an option for the patient, though it asks for years and offers no guarantee.
GraftingDemanding
Spring to summer when the bark slips · 1 to 2 years to a sellable tree; about 3 to 5 years to fruiting
Almost every blood orange in cultivation begins as a graft, the method that reproduces a chosen tree faithfully. A bud of the cultivar is set onto a rootstock in spring or summer, while the bark still slips, which keeps the fruit true to type and lends the rootstock's cold and disease tolerance. The work asks for a practiced hand, and the wait runs 1 to 2 years to a tree worth selling and 3 to 5 years before it fruits.
SeedModerate
Spring · Several years; many seedlings come true due to nucellar embryony but are slow to fruit
Sowing a seed in spring is simple enough for the curious, though nurseries leave it alone for good reason. Through a quirk called nucellar embryony many citrus seeds come true to the parent, yet the seedlings throw thorny juvenile growth and take several years to fruit. The result is a slow, unpredictable tree rather than a quick echo of the one that supplied the seed.
Myths
Blood oranges are a man-made cross or a genetically modified fruit.
The color is nothing engineered. It comes from anthocyanins, the very pigments that lend berries and red cabbage their depth. A blood orange is simply a pigmented expression of the everyday sweet orange, Citrus x sinensis, one that emerged on its own with no laboratory and no crossbreeding behind it.
Blood oranges need a hot tropical climate to turn red.
The truth leans the other way. The flesh reddens only where warm days meet cold nights, which is why the richest color belongs to regions with chilly winters, such as the slopes around Mount Etna in Sicily, rather than to a constant tropical warmth.