The whale fin snake plant (Sansevieria masoniana, also sold as the shark fin snake plant) is a snake plant with a look all its own: huge, paddle-shaped leaves that resemble the fin of a whale or shark. It isn’t always the easiest one to find, but it is a low-maintenance plant once you get the light and water right.
First, a name update. Genetic studies placed this plant in the genus Dracaena rather than Sansevieria, so it is now listed as Dracaena masoniana at NC State Extension and Missouri Botanical Garden. Both names are still in use, so it helps to know both.
Common names include whale fin snake plant, shark fin snake plant and Mason’s Congo snake plant. The “Mason” honors Maurice Mason, the English farmer and succulent enthusiast who first collected and cultivated the plant, according to Missouri Botanical Garden. The “Congo” points to where it grows wild.
It is a herbaceous perennial in the asparagus family (Asparagaceae), native to the Democratic Republic of the Congo in central Africa.
Sansevieria Masoniana Quick Care Tips
- Botanical name: Dracaena masoniana (formerly Sansevieria masoniana)
- Common names: Whale fin snake plant, shark fin snake plant, Mason’s Congo snake plant
- Pronunciation: dra-SEE-nah may-so-nee-AN-ah
- Family and origin: Asparagaceae, native to the Democratic Republic of the Congo
- Growability: Easy to grow and low maintenance
- Hardiness zones: USDA zones 10 to 11 (Missouri Botanical Garden); NC State Extension lists 9 to 11
- Size: 2 to 3 feet tall by 1 to 2 feet wide (Missouri Botanical Garden); 3 to 5 feet tall by 1 to 2 feet wide (NC State Extension). Leaves can reach 3 to 4 feet long and 8 to 10 inches wide.
- Flowering: Rarely flowers indoors; greenish-white, fragrant flowers when it does
- Light: Bright, indirect light; tolerates low light; protect from hot afternoon sun
- Temperature and humidity: Thrives at 65 to 85°F with humidity of at least 50%; avoid temperatures below 55°F
- Soil: Well-draining mix, such as perlite, coarse sand and organic matter
- Water: Let the growing medium dry out between waterings; water much less from fall through winter
- Fertilizer: A balanced liquid houseplant or cactus and succulent fertilizer in the growing season, following the product label
- Pests and diseases: Spider mites and mealybugs; root rot from overwatering
- Propagation: Division or leaf cuttings
- Safety: Toxic if ingested by people, cats and dogs
Sansevieria Masoniana Whale Fin Care Tips
Size and Growth
Size depends on who you ask. Missouri Botanical Garden lists mature plants at 2 to 3 feet tall and 1 to 2 feet wide, while NC State Extension lists 3 to 5 feet tall and 1 to 2 feet wide. Either way, the leaves are the show.
NC State says they can reach 3 to 4 feet long and 8 to 10 inches wide, and describes them as thick, stiff, waxy and dark green, mottled with lighter green.
Missouri Botanical Garden adds that each rhizome produces one or two leaves, and that clumps tend to grow wider before producing larger foliage. NC State lists the growth rate as slow, so give it time.
Iowa State Extension describes whale fin leaves as wide (8+ inches), stiff and dark green, and notes that the plant is often sold in garden centers with just one or two large leaves.
Flowering and Fragrance
A whale fin snake plant rarely blooms indoors. When it does, Missouri Botanical Garden describes an upright stalk carrying greenish-white flowers about an inch long. NC State says the flowers are fragrant, grow in clusters and appear in summer.
The plant spreads by underground rhizomes, which is how one plant slowly becomes a small colony. For more on snake plants in bloom, see our guide to snake plant flowers.
Light and Temperature
Give it bright, indirect light. NC State Extension says the plant prefers bright, indirect light and tolerates low light. Missouri Botanical Garden agrees, adding that it tolerates some shade.
Both warn about strong sun: NC State says direct sunlight can scorch the leaves, and Missouri Botanical Garden says to protect the plant from hot afternoon sun.
For temperature, NC State says the plant thrives between 65 and 85°F and recommends humidity of at least 50%. It also says to avoid cold drafts and temperatures below 55°F.
Outdoors, hardiness zones vary by source: Missouri Botanical Garden lists zones 10 to 11, and NC State lists zones 9 to 11.
In cooler climates, keep it as a houseplant. The Missouri Botanical Garden says you can move indoor plants to shady outdoor locations in summer. Keep that 55°F floor in mind and bring the plant back indoors before temperatures drop that low.
Watering and Feeding
The most important rule is to avoid overwatering. NC State calls the whale fin very drought tolerant and says it is best to let the growing medium dry out between waterings.
Missouri Botanical Garden lists its water needs as dry to medium, with regular watering during the growing season and significantly reduced watering from fall through winter.
In practice, that means checking the potting mix before you water instead of following a calendar, and using a container with drainage holes so extra water can escape.
For feeding, use a balanced liquid houseplant fertilizer or a cactus and succulent fertilizer during the growing season, and follow the directions on the product label for how much and how often.
Soil Mix and Transplanting
NC State recommends a mix of perlite, coarse sand and organic matter for good drainage and aeration, and Missouri Botanical Garden also says to use a well-draining potting mix.
Choose a container with drainage holes. Missouri Botanical Garden recommends shallow clay pots, because the roots are not deep and the large leaves can make a pot top-heavy and prone to toppling.
When should you repot? NC State says to repot when the plant is pot-bound or when the roots grow out of the drainage holes. Related reading: Tips on the Best Soil for Snake Plants.
Grooming and Maintenance
Care is low maintenance, but those big leaves collect dust. Wipe them with a damp cloth when they look dull to keep the plant looking fresh.
Related reading: our guide to the cylindrical snake plant, Sansevieria cylindrica.
Propagating Masoniana Sansevieria
NC State Extension lists division and leaf cuttings as the ways to propagate this plant, and Missouri Botanical Garden says it is easily propagated by division. Because the plant spreads by rhizomes, a clump that has filled its pot is a natural candidate for dividing.
To divide, take out a section that has both roots and leaves and replant it in fresh, well-draining mix.
For a leaf cutting, cut a healthy leaf off at the base, if you have enough leaves to spare. Set the bottom of the cut leaf in a cup of water and change the water every few days until roots form.
More on snake plants: 25+ Other Snake Plant Varieties.
Sansevieria Masoniana Pests and Diseases
Watch the watering first. NC State says root rot and black spot can occur from overwatering, and Missouri Botanical Garden says overwatering often causes root rot.
Insects to watch for: both sources list mealybugs and spider mites, and NC State also lists scale, thrips and aphids.
For mealybugs on a houseplant, UC IPM (the University of California Statewide IPM Program) says to hand-pick them or dab them with a cotton swab dipped in a solution of 70% or less isopropyl (rubbing) alcohol in water, testing a small part of the plant a day or two beforehand to make sure it does not cause leaf burn.
It says insecticidal soaps, horticultural oils or neem oil applied directly can give some suppression, especially on younger nymphs.
For spider mites, UC IPM says a water spray or mist on the undersides of leaves can help, and that insecticidal soap or oil can be used if needed, including neem oil. It advises against spraying when plants are water-stressed or when it is very hot. More detail is on its spider mites page.
Is Sansevieria Masoniana Poisonous?
Yes, it is toxic if eaten. NC State Extension rates the poison severity as low, but says the leaves and sap are toxic if ingested, to people as well as cats and dogs. For people, it lists nausea, vomiting and diarrhea, and says the sap may cause skin irritation.
For cats, NC State lists vomiting, difficulty breathing, coughing or disorientation. For dogs, it lists vomiting, lethargy, drooling, diarrhea and seizures. Keep the plant out of the reach of pets and children.
Does It Clean the Air?
Snake plants are often described as air-purifying. That idea comes from potted-plant studies done in small, sealed chambers.
A 2020 review of 12 published chamber studies, in the Journal of Exposure Science & Environmental Epidemiology, found that matching the air an ordinary building already exchanges with the outdoors would take 10 to 1,000 plants per square meter of floor space.
The review covered potted plants in general, not this species, so enjoy the whale fin for its looks and easy care rather than as an air cleaner.
Conclusion
The whale fin snake plant is a striking, low-maintenance choice for a houseplant collection, or for a garden in a warm climate. Give it bright, indirect light, let it dry out between waterings, and keep it away from curious pets.
Do you grow a whale fin snake plant? Tell us how yours is doing.
Frequently Asked Questions
What kind of light does a whale fin snake plant need?
Bright, indirect light is best, though it tolerates low light. NC State Extension says the plant prefers bright, indirect light and tolerates low light, while Missouri Botanical Garden says it tolerates some shade. NC State says direct sunlight can scorch the leaves, and Missouri Botanical Garden says to protect the plant from hot afternoon sun.
How often should I water Sansevieria masoniana?
Water when the growing medium has dried out, not on a calendar. NC State Extension calls the plant very drought tolerant and says to let the medium dry between waterings. Missouri Botanical Garden says to water regularly in the growing season and much less from fall through winter. Use a pot with drainage holes.
Is the whale fin snake plant toxic to cats and dogs?
Yes, it is toxic if eaten. NC State Extension rates the poison severity as low, but says the leaves and sap are toxic if ingested by people, cats and dogs, and the sap may irritate skin. Vomiting is among the symptoms it lists for both cats and dogs. Keep the plant out of reach of pets and children.
Can I grow a whale fin snake plant outdoors?
Yes, if you live in a warm climate. Missouri Botanical Garden lists hardiness zones 10 to 11 and NC State Extension lists zones 9 to 11. NC State says to avoid temperatures below 55°F, and Missouri Botanical Garden says indoor plants may be taken to shady outside locations in summer.
How do you propagate Sansevieria masoniana?
Use division or leaf cuttings. NC State Extension lists both methods, and Missouri Botanical Garden says the plant is easily propagated by division. It also says the plant slowly forms small colonies by spreading underground rhizomes.