Snake plants are famed for their resilience to hardship. But what if yours is turning black? This has happened to me before when I got my first snake plant. I had previously seen an overwatered snake plant, and it turned a combination of yellow and brown with a soft, mushy texture but not necessarily black.
However, I now work at a garden center, so I have a lot of first-hand expertise, and I have been able to talk directly with experts. Through my own experimentation and advice from specialists, I have discovered that it is not just overwatering, but also simultaneously cold temperatures that cause the succulent to turn black.
My own succulent was in a spot in my home (I live in a cold climate) that dipped below 50 degrees F (10C), and I was watering it when the soil wasn’t dried out enough, which turned out to be the culprit!
In this article, I’ll share with you everything I learned so you can diagnose why your snake plant is turning black and how you can save it!
We need to keep in mind that it is more the fact the soil is too damp that causes the root rot, which can turn snake plant leaves black, which is most often overwatering, but it can also be due to slow draining, boggy soil or pots that do not drain very efficiently…
One other cause of a leaf turning black is a leaf that got sunburnt! So, we need to remember to locate our snake plants in bright, indirect light.
If your snake plant leaves have turned black keep reading for how to implement the best practices of care to prevent this from happening and how to revive your snake plant…
Overwatering AND Cold Temperatures Cause Snake Plants to Turn Black
As we discussed, by far, the most common cause of snake plants turning black is due to the combination of overwatering AND cold temperatures.
We need to consider how our snake plants grow in their native environment snake plants are native to Africa, where they grow in drought-like conditions with infrequent rainfall.
If you water your snake plant more frequently than once per week, like I did, then you are overwatering it.
This is particularly true in Winter time when snake plants go seasonally dormant and slow down growth, which reduces their demand for moisture so in the Winter months watering once per month (with a good soak to encourage healthy roots) is required to avoid root rot.
My problems were compounded as I had my snake plant on a window sill, which got really cold at night. In fact, I noticed some of the leaves were actually in contact with the cold window pane, which was even colder than the ambient temperature of the room.
(If your snake plant is not growing read my article for the reasons why and how to solve it).
Temperature colder then 50 degrees F (10C) and too much water around the roots from frequent watering promotes the conditions for the fungal disease root rot which turns the snake plant leaves black.
Snake plants often turn yellow and droop as the first indication of overwatering, with black leaves indicating that root rot has occurred. The black part of my snake plant’s leaves felt mushy.
How I Saved it…
My colleagues at the garden center advised me to scale back the watering. I was taught that snake plants should be watered by soaking the soil and then allowing it to dry completely, as this replicates the conditions in their native environment.
So, whilst working at the garden center, I have experimented with how long it takes for the snake plant’s soil to dry out.
Pro Tip: Typically, I find it takes 2 weeks for it to feel completely dry, so this is a good guide, but really, to prevent our snake plants from succumbing to overwatering what I’ve found is that we have to tailor the watering schedule to the specific snake plant as there are so many variables that can determine how quickly the soil dries out.
The best way I have learned to establish the correct watering frequency for your climate is to feel the soil at the bottom through the drainage hole in the base to detect whether it is dry or moist.
(Read my article for how often to water snake plants in Winter).
If it is dry, this is the perfect time to water. If it is still moist, wait until it dries before watering.
Other than this, you can pick up your snake plant pot periodically to assess the weight. Once the soil has dried it should feel significantly light, which is a good cue to water your snake plant.
If the area of your snake plant’s leaf is black and mushy like mine was, the trick is to cut back these areas of the leaf as they do not revive, and the black mush can spread, infecting other parts of the plant.
I used a cloth soaked in disinfectant to wipe the blades of my pruners (as this prevents the spread of infection) and cut the leaf at the base of the plant.
When I first did this, I was alarmed that the wound from the pruners started oozing, but I can now assure you this is completely normal, and you should leave the wound to callous over, which, in my experience, took only a few hours.
Once I cut back the black-infected part of the plant and you have corrected your watering practices, the plant should live. Of course, this is assuming you locate it way from a window sill or any other place that could dip below 50 degrees F (10 degrees C).
If several leaves have turned black, then it can be very difficult to revive, and the plant is likely to die back.
If there is any healthy tissue on the plant, then I recommend taking cuttings for propagation.
Propagating snake plants from cuttings is very easy and has a high success rate. Watch this video for how to propagate your snake plant easily:
Drainage Dilemma: Why Slow-Draining Soils Can Turn the Leaves Black
So for us to understand why slow-draining soil can turn the leaves black, we have to undertsand how they grow in the wild…
Snake plants have adapted to growing in naturally gritty soils that do not hold onto much moisture and drain very quickly.
A classic mistake people make is when the snake plant is in ordinary potting soil, then it is likely to retain too much moisture around the roots of your snake plant and cause the leaves to turn black.
So how do we solve this? We need to plant our snake plants in soils that mimic the well draining characteristics of the soil in their native environment.
Snake plants thrive when they are planted in specially mixed succulent and cacti soil, which is available in garden centers and on Amazon.
Important Tip: Special succulent potting mixes have the exactly the right drainage characteristics for snake plants so that water infiltrates effectively to reach the roots yet drains away quickly to avoid root rot.
If you have a potting mix that stays moist for a long time after watering then I recommend replacing it with soil with some succulent and cactus soil to prevent further stress to the plant.
But I should caution that even with the right watering frequency and well-draining potting mix, it is still important to cut out any drooping leaves or black sections of leaf entirely to prevent any rot from spreading and for the plant to recover.
However, with significantly black snake plants, it may be necessary to take any cuttings you can from any remaining green leaves for propagation.
Once I replanted my snake plant not in special succulent soil, it significantly mitigated any problems with overwatering.
(Read my article, how to save a snake plant with drooping leaves).
How to Keep Your Snake Plant Happy and Healthy? Drainage is key!
So, we need to consider that snake plant leaves can turn black due to water stress because they are planted in pots without drainage holes in the base of the pot which causes water to pool around the roots.
If your snake plant is in a pot without drainage holes, then I would re-pot it immediately to save it.
We must also consider that pots without drainage holes in the base are not the only reason for snake plant leaves turning black…
- The use of saucers and trays. If you have a saucer or tray underneath your pot to prevent water from spilling, then this should be emptied frequently to allow excess water to escape rather than pool around the base of your pot, as this keeps the soil damp and causes root rot.
- Drainage holes clogged by roots or compacted soil. It is worth checking the base of your pot if you notice the soil draining slowly. Sometimes, the drainage holes become clogged with thick roots or compacted soil. With succulent and cactus soil, the potting soil is less likely to be compacted and more likely to stay porous and well-draining.
- Snake plants are often sold in the store as gifts with a decorative outer pot. This pot can prevent excess water from escaping and cause the soil to stay damp causing water stress and your snake plant leaves to turn black.
It is worth me reemphasizing as it is so important: Snake plants require the soil to dry out between waterings to prevent rot and the leaves from turning black, so it is important to plant your snake plant in the appropriate pot and ensure that excess water can escape after watering.
The same applies to snake plants that are water stressed for any other reason, in that you should cut away any black leaves back to healthy tissue and propagate from cuttings if necessary.
A Snake Plant with Black Leaves? Humidity Might be the Culprit!
As we talked about, our snake plants are native to hot and dry environments and prefer to be in rooms of low humidity.
I’ve learned that humidity can slow the rate of transpiration (water-loss) from the snake plants leaves, which is the primary way that snake plants regulate their moisture levels.
Less transpiration due to high humidity can contribute to the water stress that causes snake plants to turn black.
We need to think about whether the higher levels of humidity may not be just because of the climate but also due to the:
- Watering onto the leaves or misting the leaves. This is a classic mistake and it is contrary to the snake plants preferred dry conditions to mist the leaves. My solution is to water snake plants at the base of the plant rather than overhead to prevent creating a humid micro-climate.
- Humid rooms of the house. Snake plants generally do not like to grow in steamy rooms such as the bathroom or kitchen with lots of moisture in the air. Locate your snake plant in a dryer room.
- Humid climates. Snake plants can struggle to grow in climates with high levels of humidity, so find a breezy location for your snake plant if it is possible.
Ensuring your snake plant is in a room with lower humidity can help it recover from rot and prevent further damage to the leaves.
Consider this a virtue! My snake plant can grow in air conditioning, near sources of heat, and anywhere with a draught without causing a fuss! This is in contrast to other house plants (mentioning no names “ahem” calathea!)
Read my related articles:
Has your snake plant turned black? Have you insights into saving it? Please leave a comment below!
Key Takeaways:
- Snake plants turn black because of root rot, which occurs when there is too much moisture around the roots, caused by overwatering, slow-draining soils, or pots without drainage holes in the base. High humidity can also contribute to the leaves turning black.
- Scale back the watering, replace the soil with succulent and cactus soil, and ensure the snake plant is in a pot with good drainage.
- Locate the snake plant in a room with lower humidity and avoid steamy bathrooms or kitchens.
- Cut away any black rot from your succulent to prevent the rot from spreading and propagate from healthy cuttings if necessary.