Caring for your Whale Fin Plant (Sansevieria Masoniana)

a small potted whale fin plant, Sansevieria Masoniana, with a single leaf

The Sansevieria Masoniana is a unique houseplant with many names! Known informally as the Whale Fin plant or the Snake plant, this succulent has been recently re-classified as Dracaena Masoniana (scientific name).

Hailing from the Democratic Republic of Congo in Central Africa, the Sansevieria Masoniana is an upright grower with mottled light and dark green foliage. Hard to capture in photos, a pinkish-red tinge outlines leaf edges. 🙂

They are fuss-free plants perfect for beginners, being quite resistant to pests and diseases while enduring a range of light conditions. Whale Fin plants prefer mild indoor temperatures and drier conditions thanks to their succulent-like leaves.

In this article, we’ll let you in on all the key care aspects you need to know to help your Whale Fin thrive! 🙂

Whale Fin variegated version

potted variegated whale fin plant with a long and broad leaf in a small pot. it has bright yellow variegation and green stripes.
Copyright © 2022 Twiddle Fig & Leaf (Instagram & Facebook). All Rights Reserved. Used with Permission.

Just a quick note – if you are in the market for a Whale Fin, there are brightly variegated versions to consider. Some have leaves painted with streaks of bright yellow or bright yellow patches!

Heavily variegated Whale Fins will require higher amounts of bright but indirect light. Variegated parts of the plant lack chlorophyll, so you’ll need to give it more sunlight to compensate.

Other than that, care conditions are the same as your all-green Whale Fin plant.

Caring for your Whale Fin Sansevieria

Light

Perhaps the biggest misconception about your Whale Fin plant is that it grows best in low-light. The truth is that they are incredibly adaptable to a wide range of light and so can TOLERATE low light, but, the best, fastest growth is stimulated by bright, indirect light.

For this reason, placing your plant next to an East or West-facing window is ideal.

potted variegated whale fin plant with a long and broad leaf in a small pot. it has light and dark green mottling with long bright yellow stripes
Copyright © 2022 Twiddle Fig & Leaf (Instagram & Facebook). All Rights Reserved. Used with Permission.

Water

When it comes to watering, consider your plant’s thick, tuberous roots, and broad fleshy leaves. Roots and leaves store water efficiently, so your plant needs less frequent watering than many other houseplants like Calatheas and Monsteras.

You’ll know your Snake plant needs a drink when the top 2 inches of soil feels completely dry. Another sign is when the leaves start to wrinkle slightly, indicating that the water stores have depleted.

During the fall and winter, don’t be surprised that your plant needs significantly less water. It’s not uncommon to water 1/3 or 1/4 as often as you did in the prime growing season. But the exact frequency depends on your climate, potting mix, etc.

So, continue to abide by the Watering Rule #1: watering only when the topsoil is dry. Using this method, you won’t have to guess when your plant needs a drink. 🙂

How to water

Another important watering tip: Water slowly and deeply, thoroughly soaking your Snake plant. Allow water to saturate the soil until excess water escapes from the drainage hole. Then, empty the saucer.

Humidity

When it comes to humidity, your Sansevieria is not too fussy. 40-50% humidity is ideal, although average room humidities are okay too. This is thanks to its succulent-like leaves, which make it more tolerant to dry conditions.

A word of warning – don’t mist the leaves. The Whale Fin plant is susceptible to developing bacterial leaf spots from wet foliage. This results in a foul smell and mushy soft rot at the base of the leaf.

All things you definitely want to avoid!

close up of a whale fin plant leaf with yellow variegation
Copyright © 2022 Twiddle Fig & Leaf (Instagram & Facebook). All Rights Reserved. Used with Permission.

Temperature

Mild indoor temperatures between 65-75 degrees F (18-24 degrees C) are perfect for your Whale Fin Sansevieria.

They can grow outdoors year-round in USDA hardiness zones 10 and 11 (if you’re in the US, check your hardiness zone here.)

As usual, avoid placing your plant in the way of air vents or strong winds. They appreciate stable temperatures.

Flowers

Blooming is very rare for your Whale Fin plant when grown indoors. However, given sufficient warmth and bright indirect light, you may spot tall, whitish-green flowers growing.

These reach about 1 inch (2.5cm) long indoors, but as you can see from the photo below, can grow much larger outdoors!

a flowering whale fin plant, sansevieria masoniana or dracaena masoniana growing in the wild. flowers are greenish-cream and long
Copyright © 2022 irida73ceae, iNaturalist, some rights reserved (CC BY-NC).

Growth

Sorry to break it to you – your Sansevieria Masoniana is painfully slow-growing, so you need to be patient! When fully mature, your houseplant tops out between 1-2 feet tall (30-60 cm) and 5 inches (12 cms) wide.

The best you can do to increase its growth rate is to give it sufficient light and warmth. And maybe distract yourself with other houseplants 😛

Like Alocasias, the Sansevieria Masoniana grows from rhizomes (modified stems, like ginger) under the soil’s surface. Each rhizome produces 1-2 leaves and grows horizontally in a clumping growth habit.

Though you may start off with a single leaf, little offsets or “pups” (baby plants) will, over time, start appearing above the soil’s surface next to the mother plant. Left alone, these leaves will grow long and tall, creating a bushy look.

close up of the bottom of a sansevieria masoniana or whale fin plant in a pot with a chunky soulless mix
Copyright © 2022 Twiddle Fig & Leaf (Instagram & Facebook). All Rights Reserved. Used with Permission.

Soil or Growing Medium

An extremely free-draining potting mix is key for your Whale Fin plant. Avoid heavy, dense soils with lots of peat moss and compost – these are too water-retentive for your plant.

Given that overwatering is the MOST common problem for ailing Whale Fins, you really want a potting mix that drains exceptionally well.

We like using Noot’s soilless mix (that’s already pre-blended with perlite, coco husk, coir and chips), and adding some pumice and a handful of charcoal to lighten the mix and improve drainage.

Here’s the mix we use:

Container

A couple of tips when it comes to choosing a pot:

  • Choose a shallow but sturdy pot. Whale Fin roots do not grow deep, but leaves can get heavy, making the plant prone to toppling over. You also want a pot that’s wide enough to accommodate its clumping habit!
  • Choose a pot with drainage holes. With all that fuss over potting mix, you also need to allow the water to actually leave the pot.

Personally, we love these shallow terracotta pots.

Fertilizer

If you’re using the Noot Organic Soilless mix, these come pre-fertilized so there’s nothing extra to be done. But if you’re using soil that you received the plant in, check with the seller if the mix has already been treated with fertilizer.

Otherwise, you can apply a gentle succulent fertilizer to your Whale Fin plant, but note that they are very light feeders and react poorly to being overfertilized.

  • Choose a gentle succulent fertilizer.
  • Apply once a month at 1/4 strength.
  • Fertilize only in the spring and summer months when the plant is actively growing. Don’t fertilize at all during fall and winter.

If you see a white crust forming on the potting mix, your plant is overfertilized. Flush your plant with room temperature water for 2-3 minutes, allowing the salt build-up to wash away. Then, let the plant dry out completely before watering again.

Repotting

Being really slow growers, you won’t need to repot your Whale Fin often. Only when you notice roots peeking out of the drainage hole should you think of repotting. As a rule of thumb, this is once every 3-4 years.

Do this in spring or summer, so that your plant can recover whilst when the weather is warm and there’s plenty of bright indirect light to coax it back to good health.

close up of a single-leaf sansevieria masoniana or whale fin plant in a pot with a chunky soulless mix
Copyright © 2022 Twiddle Fig & Leaf (Instagram & Facebook). All Rights Reserved. Used with Permission.

Another tip – When the time comes, consider whether you want to take the opportunity to propagate your plant at the same time! (Read below Propagation steps).

Toxicity

According to ASPCA, unfortunately, your Whale Fin plant is toxic when ingested by animals and humans.

Plants from the Agavaceae family have sap that contains calcium oxalate raphides which is irritating to the touch. For this reason, always use gardening gloves when propagating.

When ingested, these raphides may cause nausea, vomiting, and mouth burns.

Propagation

There are a couple of easy ways to propagate your Whale Fin (but only when it’s mature!).

If you have an established plant with more than a few leaves, you can propagate your plant either through rhizome division or leaf cuttings.

Propagation by Rhizome Division

  1. The day before propagation, water your plant. Also, make sure to sterilize a knife blade with 70% isopropyl solution. Prepare gardening gloves too.
  2. Place your plant on its side and unpot your Sansevieria Masoniana. Once dislodged, use your fingers to gently tease out the soil to reveal the rhizomes.
  3. Look for a part of the rhizome that is growing at least 1 healthy leaf and has some healthy roots attached.
  4. Cut off this part of the rhizome with the clean blade.
  5. Repot the separated rhizome (with the leaf and roots) in an evenly moist potting mix. Choose a pot that is suitable for its size.
  6. Return the mother plant back in its pot.
  7. Keep both plants in a warm, humid location with plenty of indirect light.
  8. It will take about 6 weeks for your baby plant to establish itself in its new pot!
close up of the bottom of a variegated sansevieria masoniana (bright yellow and green leaf) or whale fin plant in a black pot
Copyright © 2022 north ivy plants). All Rights Reserved. Used with Permission.

Propagation through Leaf Cuttings

A unique way to propagate a healthy and established Whale Fin plant is to use leaf cuttings. Only do this when you have at least 3-4 leaves.

  1. Examine your healthy plant, and cut horizontally at the base of a healthy leaf.
  2. Place the cut leaf, cut-side down, into a water jar half-filled with room temperature water.
  3. Place the water jar in a warm spot with indirect light, and change out the water every 3-4 days.
  4. Soon, you’ll see little roots forming from the base of the leaf.
  5. When the roots grow to about 2 inches (5cm) long, plant your leaf into a moist potting mix in its permanent pot.
  6. Treat as you would any other Whale Fin plant.

Pruning

If you have a healthy Sansevieria Masoniana, there’s virtually no pruning that needs to be done. 🙂

Common Pests and Diseases

Though your Whale Fin plant is usually problem-free, no plant is 100% immune to trouble!

If you have an ailing Sansevieria, the most common culprits are scale or mealybugs, and leaf spot or blight, which arise from an overwatered plant.

Mealybugs and Scale

  • Mealybugs – appear like bits of white cotton balls with clearly segmented bodies around 1/10 – 1/4 inch (0.3-0.6cm) long. They like clustering together and are commonly found around new growth and hard-to-reach spots.
  • Scale – close cousins of the mealybugs, scale often look like immobile shell-like bumps that are clustered together, usually between 1/16 (0.2cm) to 1/8 inch (0.3cm) long. They come in many colors, but usually appear tan, black or brown.
  1. Thoroughly inspect all your plants. These bugs love to hide in hard-to-reach corners!
  2. Quarantine any infected plants away from all other plants to prevent cross-infection.
  3. Using sterilized garden shears, trim off any visibly damaged or heavily-infested parts of the stems and leaves. We use 70% isopropyl solution to sterilize our gardening tools; this is important as cross-contamination is a common cause of spread.
  4. Apply an Insecticidal Soap spray to the remaining stems and leaves. Reapply as necessary and as the instructions dictate until you see that the infestation has been eradicated.
  5. Apply a dilute neem oil solution to all other plants as a preventative measure against infestation. Neem oil disrupts the growth of larvae and prevents scale and mealybugs from feeding, growing, and reproducing.

For information on how to identify mealybugs and a step-by-step guide on killing them off, read our guide.

Leaf Spot or Leaf Blight

If your plant is infected by leaf spot or blight, you’ll need to act quickly. Here’s how to save your infected plant:

  1. First, gather and destroy any fallen damaged leaves and dispose of them securely. Growth on affected leaves can re-infect other parts of the plant or new healthy plants it comes into contact with.
  2. Isolate your plant from other plants to prevent contamination.
  3. Trim off any damaged leaves, again carefully disposing of them. Make sure to sterilize your garden shears using 70% isopropyl before and after use.
  4. Apply a fungicide that contains chlorothalonil to contain the spread of the infection. Chlorothalonil is an effective broad-spectrum fungicide.
mottled whale fin plant with dark and light green variegation in a pretty patterned pot.
Copyright © 2022 novegetablesnicole. All Rights Reserved. Used with Permission.

Overwatered Plant

For more info on saving an overwatered plant, check out our step-by-step guide.

Also, make sure you are using an extremely well-draining potting mix! Common indoor soils will not do – See the Soil section for our preferred mix.

Frequently Asked Questions

Is the Whale Fin Plant rare?

The Sansevieria Masoniana is not common, so can be considered somewhat rare. They also tend to be expensive as they are notoriously slow-growing.

You’ll need to check online for reputable sellers. One of our favorite places to purchase rare and exotic houseplants is Etsy.

If you happen to live in Singapore, do check out Twiddle Fig & Leaf!

Are they good indoor plants?

Yes. Sansevieria Masoniana is well-adapted to indoor temperatures. Also, according to a 1989 NASA study, a benefit of growing the Whale Fin plant indoors is that it purifies the air around it. In particular, it removes small amounts of benzene and formaldehyde.

For the sake of transparency – the air-purifying aspect of these plants is arguably too small to notice a difference if you have just a few plants. We just think it’s a good excuse to buy more! 🙂

Other Succulent-like Houseplants you may Love

water droplets on a dracaena margina plant
Dracena Marginata, a close cousin of the Whale Fin plant

Wrapping Up

The Whale Fin plant is an easy succulent for beginners. The key thing to note is to not overwater your plant, and choose a mix that is extremely well-draining. Avoid heavy peat mixes or mixes with too much compost.

While your Sansevieria can endure low light conditions, it does best in bright, indirect light. Fertilizing must be done sparingly – a gentle succulent fertilizer at 1/4 strength, applied once a month during the growing season only. Less is more!

Deborah

Deborah is a plant enthusiast and founder of Gardening Collective.