Tree · Rutaceae
Mandarin Orange
Citrus reticulata
Give it full sun, free-draining soil, and shelter from hard frost, and a mandarin tree sets fragrant white blossom and loose, easy-peel fruit.
Full sun
Every 5–10 days
55–100°F · 13–38°C
USDA 8–11
Overview
The mandarin is the easy-peel, loose-skinned member of the citrus family, its thin rind lifting away in one soft piece from segments that slip apart clean. It is the parent of clementines, satsumas, tangerines, and a long line of hybrids, and it traces back to southeast Asia. The small evergreen tree carries glossy leaves the whole year and, in early spring, opens fragrant white blossom that gives way to fruit ripening through fall and winter.
Up close the tree reads as compact and dense, its glossy green leaves crowding the branches and catching the light. It wants full sun, well-drained soil, and steady moisture, and it holds its shape whether rooted in the ground in mild regions or set in a large pot moved under cover when the cold rolls in. Most fruiting mandarins are grafted, so the named variety above the graft joins a tough rootstock at a swollen union near the base of the trunk.
Cold is the one thing the wood cannot brush off, and how well it holds depends on the type. Satsuma stands out for cold hardiness, its branches taking brief dips that would blacken most citrus, while clementines and the hybrids want a warmer, sheltered spot. Match the variety to your winters, and the small, round, bright-skinned fruit follows in its season.
Care
The short version: full sun, free-draining soil rich in organic matter, and water that keeps the roots moist without ever sitting wet. Feed with a citrus fertilizer through the growing season, prune only lightly, and shield young trees from hard frost.
Light
Mandarins want full sun, ideally 8 or more hours a day, which ripens the fruit sweet and packs the canopy with glossy, close-set leaves. They will take a little partial sun, but shade thins that dense green crown and cuts the crop.
Water
Let the top inch (3 cm) of soil dry between waterings, then soak deeply, roughly every 5 to 10 days depending on heat and pot size. Young and container trees drink more often, while established in-ground trees ride out dry spells but set the best fruit on steady moisture. Soggy roots are the thing to avoid, since citrus hates them.
Soil
Plant in well-drained sandy loam with plenty of organic matter worked through. A slightly acidic pH of 6.0 to 6.5 keeps the micronutrients within reach of the roots, and sharp drainage counts for more than richness, since standing water rots them.
Temperature
Mandarins live across a wide band, from about 55°F to 100°F (13°C to 38°C). They do their best work in warm weather, but hard frost is the real threat to the wood, so pick a cold-hardy type or stand ready to protect the tree when the temperature drops.
Humidity
Average humidity around 40% to 60% suits them, with no misting needed. Good airflow moving through the leafy canopy does more than any target number, since it keeps pests and mold from settling on the blades.
Feeding
Feed from spring through late summer while the tree is in active growth, using a citrus fertilizer that carries micronutrients. The magnesium, manganese, iron, and zinc in a citrus blend keep the leaves an even deep green instead of the yellow, blotchy look a bare diet brings.
Pruning
Keep pruning light. In late winter to early spring, take out dead, damaged, or crossing branches and any suckers rising below the graft union, since those suckers spring from the rootstock and not the fruiting variety above.
Repotting
Move container trees into a larger pot every 2 to 3 years, or when the roots circle the inside, push out the drainage holes, or water races straight through. Refresh the mix at the same time to keep growth steady and the leaves green.
Size & spacing
A mandarin matures into a small tree of about 10 to 20 feet (3 to 6 m) tall with a rounded spread of 8 to 15 feet (2.4 to 4.5 m). Give it that much open room, or keep it smaller and shapely in a large container.
When to plant
The mandarin keeps a long, slow clock across the seasons. It goes into the ground in spring once the danger of frost has passed, breaks into fragrant white blossom in early spring, and swells its round fruit to full color from fall into winter, roughly November through January.
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: Blooms in early spring; fruit ripens fall to winter (about November to January)
Hardiness
USDA hardiness zones: 8–11
Temperature: down to -12°C
Troubleshooting
Most mandarin trouble shows in the leaves first, painted plainly across the blades, whether from a missing nutrient, a cold snap, or insects clinging underneath. Read those early marks on the foliage and you can step in before the tree loses ground. Match what you see below, then act while it still helps.
Yellowing blades laced with green veins
When the leaf blade fades to pale yellow while a fine net of veins holds its deep green, the tree is short on micronutrients, usually iron, manganese, or zinc. The trigger is usually soil gone too alkaline for the roots to draw them up. Ease the pH back toward 6.0 to 6.5 to fix the soil, and a chelated micronutrient foliar spray restores the even green sheen across the blade.
Fix:
- Apply a chelated micronutrient foliar spray
- Adjust soil pH toward 6.0 to 6.5
Browned leaves falling and twigs shriveling after cold
Leaves that curl, turn brown, and let go, with slim twigs shriveling behind them, mark freeze or frost injury in the wake of a hard cold event. The dead-looking wood can still hold live buds, so it stays on the tree until spring reveals which stems push fresh green and which have truly dried out. A cover on freezing nights and a cold-hardy type such as satsuma keep the tissue from browning in the first place.
Fix:
- Wait until spring to prune out clearly dead wood
- Provide cold protection during freezes
Glossy leaves dulled by a sooty black film
A powdery black film that dulls the usual gloss of the leaf is harmless in itself, since it grows on the sticky honeydew dropped by sap-sucking insects such as aphids, scale, or whitefly. The insects cling to the leaf undersides and along the stems, and rinsing the blade lifts the tacky coating away. Horticultural oil or insecticidal soap clears the insects, and ants are worth tracking too, since they guard these pests for the honeydew and turn off the predators that would help.
Fix:
- Wash foliage to remove mold and honeydew
- Apply horticultural oil or insecticidal soap
Toxicity
The peeled, juicy flesh is a healthy snack for people, but the rest of the plant is a different story for animals. The oily rind, the glossy leaves, the stems, and the small seeds hold essential oils and psoralens that irritate the gut and the skin. Keep peelings and prunings away from pets and grazing animals, and call a vet if a large amount goes down.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds
Safe for
People
Cats Mild
A cat that bites into the oily peel or a glossy leaf usually turns up with an upset stomach, showing vomiting, loose stool, and a flat, low mood. Where the oils wet the skin, they can leave a red, itchy patch.
Dogs Mild
A dog into the pithy peel, the leaves, or the slick seeds tends to hit mild stomach trouble, mostly vomiting and diarrhea with a stretch of sluggishness. The oils may redden the skin as well, though most dogs shrug off a small nibble.
Horses Mild
The oils and psoralens packed into the peel and the leathery leaves leave a horse with an irritated gut and a dull, off-feed spell. Horses rarely go for citrus, so trouble usually follows bright trimmings left within reach.
Rabbits Caution
The peel, the leaves, and the small seeds all carry the same irritating oils, so they stay clear of the hutch. A little of the juicy flesh now and then still makes a fine treat.
Livestock Caution
Goats, sheep, and cattle can sour on the sharp oils in the peel and the cut prunings, with a dropped appetite the first sign. Clippings belong away from the pasture, not left for the animals to browse.
Birds Caution
The fragrant oils crowded into the peel and the glossy leaves sit poorly with birds, so a small taste of the flesh is the limit and the rind stays out.
People Flesh safe
The bright, juicy segments are a healthy snack and safe to eat. Working through a heap of oily peel can leave sensitive skin tingling or sun-sensitive, so a wash after a big batch clears the residue.
The fruit flesh is generally low risk, but peels, leaves, and seeds contain irritating essential oils
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
Mandarin covers a wide family of easy-peel citrus, from the cold-hardy satsumas with their loose skins to small, round clementines and a run of hybrids. These are the ones worth knowing by name.
Satsuma (Citrus unshiu)
The most cold-hardy mandarin, its loose, easy-peel skin slipping off nearly seedless segments, and its wood holding through brief dips near 15°F (-9°C).
Owari
The leading satsuma cultivar, cropped commercially across northern Florida for the steady, heavy loads of fruit it sets.
Clementine
A small, round, sweet mandarin of the Mediterranean group whose thin, easy-peel skin made it the lunchbox favorite.
Tangelo
A mandarin crossed with grapefruit or pummelo, its flesh sweet with a bright, tangy edge running through it.
Tangor
A mandarin crossed with a sweet orange, its flavor deeper and fuller in the mouth than either parent.
How to propagate
Mandarins are multiplied two ways, and the choice comes down to whether you want the very same fruit you started with or a slow experiment.
GraftingModerate
Spring or late summer · Bears fruit in about 2 to 4 years
Grafting is the commercial standard, and it earns the name. Worked in spring or late summer, it binds a slip of the chosen variety onto a vigorous, disease-resistant rootstock, and the joined tree rises straight and sets true-to-type fruit in about 2 to 4 years. The union takes a steady hand, but nothing else gives the same reliable crop.
SeedEasy
Spring · Several years and may not be true to type
A seed dropped in spring sprouts easily enough, but it asks for patience and a gambler's nerve. Mandarin seeds are often polyembryonic, yet the seedlings rise slow and uneven and can take several years to fruit, often not true to the parent. It is a fun experiment, not the way to copy a variety you love.
Myths
Citrus is completely safe to share with cats and dogs.
The ASPCA lists orange and citrus as toxic to pets, since the peel, the leaves, and the seeds hold essential oils and psoralens that upset the stomach. Only the juicy segments are low risk, and then in small amounts, so the oily rind and foliage are the parts to keep from cats and dogs.
All mandarins are equally tender in the cold.
Hardiness runs across a wide range in this group. Satsuma mandarins hold through brief temperatures near 15°F (-9°C), well past what most citrus wood can take, which is why they are the type to reach for in a borderline climate.