Houseplant · Cycadaceae
Sago Palm
Cycas revoluta
A stout-trunked cycad crowned in stiff, glossy, feather-like fronds, and carrying a toxin that can kill a pet.
Bright indirect
Every 7–14 days
48–86°F · 9–30°C
USDA 9–12
Overview
Up close, the sago palm is all firm lines and shine. A thick, stout trunk rises like a rough column and opens into a rosette of stiff, glossy fronds, each one a long feather split into narrow, rigid leaflets that arch outward. Though it mimics a palm, it is a cycad, a form held nearly unchanged since the age of the dinosaurs, and indoors it keeps that compact, symmetrical crown for years.
New growth is the sight to watch for. Once a year the center of the crown unfurls a single flush of fresh fronds, a fresh green before they stiffen into the same hard gloss as the older leaves. The plant works slowly, so that yearly ring of new leaves is the clearest mark of its unhurried pace.
Not every part is just for looking. Every portion of the sago palm is severely poisonous, and the seeds hold the most, so despite the handsome form it is unsafe around pets or small children who might chew it. Where that danger is absent, its stiff, glossy crown keeps its shape and shine longer than almost any other plant indoors.
Care
The short version: this stiff, glossy cycad wants bright indirect light, a gritty, fast-draining mix, and water only after the top half of the soil has dried. It takes a palm fertilizer in the growing season, grows slowly, and every part of it is toxic to pets and children.
Light
In bright, indirect light the fronds hold their tight, even form and hard shine, and the plant takes some direct sun once acclimated. A bright window is the place for it indoors. Starved of light, the new fronds stretch out thin and weak instead of stiff.
Water
Let the top half of the soil dry before watering again, which usually means every 7 to 14 days. This drought-tolerant cycad turns soft and rotten at the base in soggy soil or poor drainage, so err dry. When unsure, wait.
Soil
Root it in a sandy or loamy mix that drains fast, since standing moisture is what breaks this plant down. A slightly acidic pH of 5.5 to 6.5 keeps nutrients, manganese especially, within reach of the roots. Coarse grit opens a mix that stays wet.
Temperature
The fronds stay firm and green across 48°F to 86°F (9°C to 30°C), a span that covers most rooms. Frost is another matter, so a sago summered outdoors comes inside before the first cold nights bite.
Humidity
Average household air keeps the foliage in good order, with no set figure to hit. In very dry air, fine spider mites can dull and speckle the leaves, so a little added moisture nearby keeps them off.
Feeding
Through the growing season, spring into summer, feed a complete palm fertilizer. Pick one with manganese and other micronutrients, because without it the newest fronds come in yellow and frizzled, the disorder called frizzle top.
Pruning
Cut sparingly. Take off only the fully dead or badly damaged lower fronds and leave every stiff green leaf in place, because the plant replaces lost foliage at a crawl.
Repotting
Repot only every few years, or once the roots coil through and fill the pot. This slow cycad sits happily somewhat pot-bound, so constant repotting sets it back more than it helps.
Size & spacing
In open ground the trunk and crown can reach 3 to 10 feet (90 cm to 3 m) tall and spread about as wide. Confined to a pot indoors the plant stays far smaller, building that size over many slow years.
Troubleshooting
A sago palm shows its troubles right on its surface, in the color and texture of the fronds or in the firm or softening feel of the trunk base. Most problems trace to overwatering or a nutrient the roots cannot reach. Match the look below to what you see, and act early, because this slow plant is slow to push out replacement growth.
Yellowing fronds above a soft, mushy, rotting base
Fronds fading to yellow above a base gone soft and mushy are the mark of root and crown rot, driven by too much water in soil that holds it. Cut back the watering and let the mix dry, move the plant into a gritty, sandy blend, and if the rot is fresh, pare away the mushy tissue and repot into clean, fast-draining media. It must never stand in water.
Fix:
- Reduce watering and allow the soil to dry
- Improve drainage with a gritty, sandy mix
- Remove rotted tissue and repot into fresh well-drained media if rot is caught early
New fronds unfurl yellow, then brown and frizzled
When only the newest fronds come in yellow and curl into a frizzled, brown tangle while the older leaves stay green, the cause is manganese deficiency, the look called frizzle top. It appears where the soil pH has risen above 6.5 and shut the manganese away from the roots. Water manganese sulfate, not Epsom salts, in under the canopy, and feed a complete palm fertilizer so fresh growth comes in clean.
Fix:
- Apply manganese sulfate (not magnesium sulfate / Epsom salts) under the canopy and water in
- Use a complete palm fertilizer that includes manganese
- Correct excessively high soil pH
Bumps, cottony tufts, or webbing dulling the fronds
A sticky glaze, small raised bumps, or white cottony tufts along the fronds signal scale or mealybugs, while fine webbing and a dusty, pale stippling across the leaves signal spider mites that build up in dry air. Wipe or wash them from the fronds, then treat with horticultural oil or insecticidal soap. More moisture in the air turns the mites back.
Fix:
- Wipe or wash off pests
- Treat with horticultural oil or insecticidal soap
- Raise humidity to discourage spider mites
Toxicity
Behind the polished fronds sits real danger. The sago palm is a cycad, not a true palm, and every part of it, trunk, frond, and seed alike, holds cycasin, a potent toxin that attacks the liver. The seeds carry the highest load, and a single one can kill a dog or cat. Keep the plant, any dropped fronds, and every seed well out of reach of animals and children, and treat any suspected mouthful as an emergency.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds · People
Cats Severe
For a cat, no piece of this plant is safe, and the seeds are the most poisonous part of all. A cat that chews even a scrap may vomit, pass dark bloody stool, and yellow with jaundice as its liver fails, and many die despite treatment.
Dogs Severe
Dogs are pulled toward the seeds, and one or two are enough to kill. Look for vomiting, dark tarry stool, a heavy new thirst, bruising, and the yellow stain of liver damage, which can slide into fatal liver failure within days.
Horses Severe
The cycasin that poisons cats and dogs strikes horses just as hard. Vomiting, bloody diarrhea, jaundice, and clotting problems set in as the liver fails, and the end is often death.
Rabbits Severe
A rabbit has no guard against this toxin either. Even a small nibble of a frond or seed can destroy the liver and turn fatal, so keep the whole plant and every trimming far out of reach.
Livestock Severe
Cattle, goats, and sheep that crop the fronds or seeds take severe liver damage and often die of it. Keep grazing animals away from any sago palm growing within reach of a pasture or paddock.
Birds Severe
Birds are no exception. The cycasin loaded into the seeds and foliage is just as deadly to them, so a pet bird should never reach the plant or its shed seeds.
People Caution
No part of the sago palm is food, and the seeds above all can cause severe liver damage if eaten. Keep children well away, handle the seeds with care, and call poison control at once if any piece is swallowed.
Keep the plant, fallen fronds, and especially the seeds well out of reach of pets and children; wash hands after handling and dispose of trimmings and seeds securely.
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 is only one look to know here. The sago palm grown in homes is almost always the single classic species, so its stout trunk and stiff, feathered crown are the form you will meet.
Cycas revoluta (king sago)
This is the classic species, a thick, stout-trunked cycad topped with a symmetrical crown of stiff, glossy, feather-like fronds, palm-like in outline yet an ancient gymnosperm at heart.
How to propagate
A sago multiplies from its own base and its seed, though both go slowly, matching a plant that grows at a crawl. Two routes are open, one easy and one slower, and each means handling toxic tissue with care.
Offsets & pupsEasy
Spring to early summer · Several months to a year or more, as the plant is very slow-growing
The easiest increase comes from the basal offsets, the small pups that swell around the foot of the trunk, prised away and rooted in spring or early summer. The pace is glacial, and a single pup can take several months to a year or more to root and grow on its own.
SeedModerate
When fresh seed is available from a pollinated female plant · Several months to germinate and well over a year to establish
Raising one from seed runs slower still and calls for both a male and a female plant, since sago palms are dioecious. Fresh seed can take several months to sprout and well over a year to establish, and the seeds are highly toxic, so handle them with care and keep them clear of pets and children.
Myths
It is called a palm, so it looks and behaves no more dangerously than any other houseplant palm.
The likeness is only skin deep, because this is a cycad, not a palm. Where the true palms are harmless, every part of a sago, from trunk to frond to seed, holds cycasin, and swallowing it, the seeds most of all, can cause fatal liver failure in pets and people alike. It stands among the most poisonous plants you can keep indoors.