The Philodendron crassinervium is a climbing perennial that ranks among the less popular species in the genus. Not many people know about it. Nor do they seem to care about it.
Maybe because it does not look like many of the other philodendrons. Although it does have quite a bit of resemblance to the Philodendron longilaminatum.
In any case, this is an epiphytic plant that features long, narrow, lance-shaped leaves that point upwards. It also has a prominent midvein that is light green.
More importantly that midvein stores water which allows the plant to tolerate dry periods better than other philodendrons.
The leaves can reach about 3 feet long and 10 inches wide.
You’ll also likely see red aerial roots as the plant grows. Although these tend to turn more brown as it ages.
Like other philodendrons, the Philodendron crassinervium is native to South America, particularly Brazil. So it is used to tropical weather.
Philodendron Crassinervium Plant Care
Light Requirements
The Philodendron crassinervium appreciates medium to bright light provided that it is not exposed to direct sun. While it prefers natural light to artificial lighting too much intense sunlight can burn its leaves.
This is because the plant is native to the tropical forests of Brazil where it lives under the larger trees and plants. Therefore, it gets shaded from the harshest rays of the sun. Although it still receives ample amounts of light.
This makes an east facing window perfect for the plant indoors. It also does well up to about 10 or 12 feet away from the window as long as the room is bright.
If you place it in near a south facing widow make sure to filter the light or keep the plant at least a few feet away from the window itself. The same is true for a wester exposure especially in the afternoon which is when the sun comes from that direction.
Temperature
The Philodendron crassinervium enjoys moderate to warm climates since that is what is it accustomed to in its native habitat.
Although, compared to other philodendrons, it is more tolerate of the cold. But not by too much.
It can withstand temperatures as low as 50 degrees Fahrenheit without any problems. And will likewise take climates up to the high 90s without any issues. But given a choice, it thrives when the weather is moderate (65 to 75 degrees).
That said, it cannot tolerate 45 degrees or lower which is why you’ll usually see the plant growing outdoors in USDA Hardiness Zones 9 to 11.
On the hotter end, leaving in temperatures over 100 degrees for prolonged periods of time can increase its stress level. If you do this, make sure to keep it hydrated. But a better choice would be to move it somewhere with less heat.
Humidity
High humidity is what the Philodendron crassinervium likes. Ideally give it between 60% and 80% for best results. This is when it will grow the best, produce its most beautiful looking leaves and get bigger as well.
However it can tolerate lower levels as well. This makes it easier to care for indoors.
That said, if your home has dry air, it is a good idea to check the plant’s leaves for any browning especially in the edges and tips.
Lack of moisture in the air will cause the leaves to get dry as well. Although if you water it sufficiently it should be able to tolerate these conditions a little better.
I do suggest picking up a digital hygrometer to keep track of humidity. It is inexpensive and I check it every morning. This allows me to have a mental note of what the humidity has been recently.
It also lets you observe your different houseplants and how to look and respond to varying humidity levels. After a while, you already know what to do and which plants to help if the weather forecasts predicts for lower humidity in the next few days.
The two simplest ways to increase humidity (if you have dry air in your home) are misting and using a humidifier. The former does take more work. The latter is more costly.
So, if you prefer something that is free and is more passive, here are a few options.
- Move the plant to the bathroom or spot with higher humidity (every home has drier areas and those with more moisture)
- Group it with other plants. The more plants you have the more effective the humidity boost.
- Place the plant in a water tray on top of pebbles.
How Often to Water Philodendron Crassinervium
The Philodendron crassinervium is fairly drought tolerant as it is able to store water in its midrib during the dry season.
If you look closely, you’ll notice the midrib is very visible and a bit fat. That’s because of the moisture it keeps there.
This means it is more amenable to drier conditions. On the other hand, like other philodendrons, the Crassinervium is sensitive to too much water.
So, you want to stay on the safe side of things.
This means waiting for the top 2 to 3 inches of soil to dry out before you add more water. This will reduce the risk of watering.
You can likewise wait a little longer (all the way until the soil is 50% dry) before watering. The plant won’t mind as long as you don’t let it go completely dry.
When adding moisture, it will appreciate deep watering. That is, giving the soil a gentle stream of water until the entire root ball is soaked. This will allow the roots to get a lot of water.
Once the liquid drips from the bottom of the pot, stop adding moisture. And let the plant drain immediately. You want to allow it to completely drain any excess liquid before putting it back in its spot.
Altogether, these steps will prevent overwatering.
Alternatively, if you find yourself struggling with overwatering, you way want to check out LECA balls. These clay balls absorb water. And you can substitute then for soil.
This way you’ll be watering from below in a passive manner. All you need to do is leave the pot with LECA (and the plant in it) in water. And, the LECA will absorb only what’s needed for that moment.
When the water runs out refill. This way, you don’t need to regularly water your plant.
Philodendron Crassinervium Potting Soil
To avoid overwatering, the best soil for the Philodendron crassinervium is a medium that drains moisture well. It also needs to be light and airy so there’s good circulation of oxygen that reaches the roots. Together, this will prevent root rot.
For this reason many home growers are using LECA balls. These look like brown marbles. Thus, they give you lots of open spaces in the container for water to drain and air to reach the roots.
If you prefer using soil, I highly recommend picking up an Aroid mix if your nursery carries one. If not, you can use this recipe that works really well for my philodendrons.
- 1 part potting mix
- 1 part orchid bark
- 1 part perlite
- 1/2 part horticultural charcoal
You can likewise replace the potting mix with peat if you prefer going soilless.
On the other hand, avoid very heavy or dense soils that will retain moisture. This will keep the plant’s roots in water which prevents them from getting enough oxygen.
This is a recipe for root rot (at least for your Philodendron crassinervium).
Does the Philodendron Crassinervium Climb?
Yes, the Philodendron crassinervium is epiphytic in nature and will climb if given the chance. This allows it to live like how it would in its native habitat.
And, by keeping it happy, you’ll see it grow into a larger, taller plant with bigger leaves. Also, when allowed to climb, you’ll notice it grow aerial roots.
Fertilizer
The Philodendron crassinervium is not a big feeder. Thus, it is fairly low maintenance when it comes to fertilizer. The plant is also a bit more tolerant that other philodendrons when it comes to salt.
Therefore, it won’t get affected as easily as other species if you overfertilize it (which leaves more salt residue).
That said, overfeeding nay houseplant is never a good thing. So, avoid it if you can.
As far as fertilizer goes, feed your Philodendron crassinervium once a month during the spring and summer. You can use an all-purpose liquid fertilizer that’s diluted to half strength. Also, don’t apply plant food of dry soil.
If the soil is dry, water first before you apply fertilizer. This will reduce the risk of fertilizer burn.
If you see that the plant is not growing as much as it should, you can increase the frequency to once every 2 weeks.
There’s no need to feed it during fall and winter.
Pruning
The Philodendron crassinervium is a beautiful plant that can grow to between 10 and 13 feet in its natural habitat. Its leaves can also reach a little over 3 feet in length and have a width of nearly a foot wide.
But grown indoors and in a container, does not grow anywhere as big as that. This makes it more manageable. And you can enjoy it on the tabletop for a while.
Eventually, it will end up as a floor plant. That said, it takes a while since it is a slow grower.
Since the plant is epiphytic in nature, giving it a moss or burlap pole to climb on is a good ideal. This will help maximize its growth and optimize its health.
Pruning is not really needed early on when the plant does not have a ton of leaves. When it gets a bit bushy, you can trim it back a bit.
Similarly, pruning is helpful in shaping and controlling the size and with of the plant as it is gets bigger.
How to Propagate Philodendron Crassinervium
The Philodendron crassinervium is easily propagation from stem cuttings. This makes it easy to grow new plants from your parent plant.
All you need to do is take a stem and plant it. Eventually this stem will grow into a new plant (that is a clone of your existing one).
The best part is, you can cut many stems at a t time and grow several young plants simultaneously.
Here’s how to propagate Philodendron crassinervium from stem cuttings.
- Choose a healthy stem. You’re looking for one with at least one node or aerial roots. Ideally, the stem has one or more leaves as well.
- The bigger your plant, the bigger the stem you’ll take. But this also gives you the option to take bigger stems that branch out to smaller ones. Or use one of the higher stems. Either way works.
- If you want to propagate a few plants at the same time, pick that number of stems and each will be planted in their own pots later.
- Once you’ve selected the stem or stems, cut them from the mother plant. Use as sterile pair of scissors, pruning shears or a knife. And cut just below the node or aerial roots.
- If the plant has aerial roots, and want to grow it in soil, you should use sphagnum moss and keep it moist. This will help them grow longer and healthier.
- Otherwise, you can choose to propagate in water. Aerial roots will produce water roots (underground roots) which you can use to plant into the soil. They also help speed up the process and increase propagation success
- That said, you don’t need a stem with aerial roots. As long as you have a leaf node, you’re good.
- Place the cutting into water. I like to use a glass or transparent container when doing this as it lets you watch the progress of the roots.
- Once the roots get past an inch long, you can move it to a pot with soil. You can likewise wait until the roots are even longer (2 or more inches) before moving.
How to Repot or Transplant Philodendron Crassinervium
The Philodendron crassinervium grows fairly slowly so it takes about 2 or so years before you need to repot. In its juvenile stage, repotting will happen more frequently as the plant grows in size. But once it matures, this takes a bit longer.
When repotting, choosing the right container is very important. Drainage is essential because philodendrons in general, including the Crassinervium, are susceptible to overwatering.
So, in addition to watching your watering frequency and using the right soil, the pot needs to be able to let the excess moisture escape. Without drainage holes, the liquid will pool at the bottom of the container.
The best time to repot is during spring or early summer. Avoid very hot or very cold days because this increases the level of stress the plant experiences. They also get transplant shock from the move so adding to that is not something you want to do.
Is It Toxic/Poisonous to Humans, Cats & Dogs
All the parts of the Philodendron crassinervium including its leaves are toxic. That’s because the plant contains calcium oxalate crystals which are poisonous to humans and animals when consumed.
Similarly, if you have sensitive skin, it is a good idea to wear gloves and wash you hands any time you work with the plant. Its sap can cause skin irritation in some people.
Problems & Troubleshooting
Yellow Leaves
Too much water is often the cause of the yellow leaves. But it is not the only reason why foliage turns this color. However, it is the most dangerous.
So, any time you see yellow foliage, suspect overwatering first and eliminate other causes like too much light, fertilizer or natural aging.
The easiest way to tell is to check the soil. Wet, mucky or soggy soil is a bad sign that you don’t want to ignore. It means the soil is getting too much liquid or is not draining it well enough.
This means you’re either watering too often or the soil you’re using is retaining too much water. Fix whichever the cause is.
And if you suspect this has been happening for a while now (because you haven’t changed your watering routine), it is a good idea to unpot the plant and look at the roots.
The goal is to check for any rotting roots. Black, mushy, smelly or soft roots mean they’re damaged or rotten. Prune these and repot the plant in fresh dry soil if you see any.
Then adjust the kind of soil you use or your watering schedule, whichever may have caused the issue.
Pale Colored Leaves
Pale colored leaves are often caused by one of 3 things.
Lack of sunlight – this is the most common. If the plant is in a dim spot or somewhere that only received sporadic light, move it to somewhere brighter. This will help the plant grow and regain its color. Keep it mind that plants need light for photosynthesis. In turn, photosynthesis supports the plants since it is how it creates its food for energy. So, lack of sun means a low energy plant.
Not enough overall nutrition – similarly, lack of supplementation not only slows growth but also causes less coloration. Make sure you’re feeding it enough.
Specific mineral deficiency – if you’re feeding the plant enough, check the label to see if the product contains calcium and magnesium. Philodendrons need these minerals. And without them, leaves will turn pale.
Pests
Thrips, mealybugs, aphids and scale are all problematic bugs that can come and bother your Philodendron crassinervium. They are very small and tend to hide under the leaves and in the junctions between the leaves and stems.
So, make sure to inspect the plant regularly. Dusting and cleaning the leaves will also help you spot them early as well as prevent these pests from coming.
They are attracted to dust so by keeping the plants clean, you reduce the risk.
Diseases
Root rot is the very serious result of overwatering. And it is the #1 cause of houseplant death. This is why watering, soil and the pot all need to helps with drainage and aeriation when it comes to your Philodendron crassinervium.
They all work to prevent root rot.
Erwinia blight is another common problem that philodendrons experience. It is a bacterial infection that affects the leaves. And is cause by too much moisture.
But this time on foliage.
