Learn about the stunning philodendron black cardinal, a variety of erubescens with leaves that vary in color from a deep burgundy to a deep green. Find out how to help this dark variety thrive as a houseplant.
How do you take care of a philodendron black cardinal?
So I’m trying to write care posts for the most common varieties of philodendron erubescens you might find—because man can they be super confusing! Today’s plant, the black cardinal, is one I thought I bought a while ago.
It was labeled and sold to me as a black cardinal. But after getting home and having my doubts, I posted on a local plant group and did some sleuthing online. Turns out I’d purchased what is almost certainly a philodendron rojo congo.
The rojo congo is pretty, but I really wanted to black cardinal. So when one of my favorite local plant shops got one in stock (Take Root plants), I snagged it. And man is it lovely!
Although this one looks a lot closer to a traditional black cardinal, it still has some differences. I am not sure if that’s because it isn’t as mature, but I’ll surely be watching as it grows.
What is a philodendron black cardinal?
The philodendron black cardinal is a hybrid plant of multiple other types of philodendrons. The inventor, Cora McColley, crossed a philodendron erubescens, philodendron wendlandii, philodendron hastatum (silver sword), philodendron imbe, philodendron fragrantissimum, and an unnamed species to achieve the final result.
The patent for the plant was filed in the early 1980s; however, it has long since expired. So it’s possible that the plant has experienced some additional evolution over decades of breeding, making it even more difficult to ID.
Black cardinal is characterized by thick, leathery leaves that emerge brick red and harden off to dark leaves with tinges of deep green, red, and brown. Together, these give the leaves quite a dark look that approaches black in the right light.
Is philodendron black cardinal rare?
I would not say that the philodendron black cardinal is rare. I purchased mine locally for under $20, but I had to wait a while for it. I was not finding a healthy-looking one in stores, and I didn’t want to order it online.
I’d say the main issue with buying a black cardinal isn’t its rarity—it’s the difficult of finding one that is mislabeled! And I don’t really fault sellers for this because the different varieties of erubuscens can look so similar, especially in juvenile forms.
Try to buy from a reputable seller and look at lots of pictures. Keep in mind that younger forms of the plant can look a lot more green than you might be expecting, too.
Does black cardinal need sunlight?
Yes, all plants need some light, it’s just a matter of how low of a light level they can withstand. The original patent for black cardinal says that it can withstand particularly low light levels.
However, it will do best in bright, indirect light. Close to a sunny window is a nice option. Some direct morning sun should be fun, but avoid too much direct afternoon sun. It can burn the leaves.
Outdoors, keep it in the shade under a dense tree canopy, a shade cloth, a pergola, or a deck. Dappled sunlight is fine. You just want to avoid scorching the leaves.
If you keep the plant indoors and do not have great light, you may choose to add a grow light. Philodendrons can do quite well with grow lights, so this is a nice option. Don’t place it too close to the grow light and experiment with intensities while monitoring the plant.
Whatever lighting you choose, if the plant is getting light only from one side, make sure to rotate it every few weeks. Otherwise, it will grow lopsided. That happened to my philodendron birkin, and I had to add a stake to straighten things out.
How often should I water a black cardinal?
Water your black cardinal when the top several inches of soil dries out. For me, this generally means weekly in the spring and summer and every 2 weeks in the fall and winter.
You can check the soil using a moisture meter or your finger. When you water the plant, do so thoroughly. I like to water my plants in the shower or sink so I can rinse off all of the foliage as well.
This helps keep the thick, glossy leaves looking their best by cleaning off dust and debris. Let all of the water drain from the pot’s holes before putting your plant back.
Note that the patent for this plant also says that it can withstand low moisture content very well, so you might be able to stretch it farther before watering it again. However, I haven’t tried this, so I can’t say how it responds to a bit of deprivation.
Any well-draining soil designed for houseplants or indoor plants is great. This will help to encourage drainage, keep the soil light, and retain the appropriate amount of moisture.
If you plant your black cardinal in something that is too dense, it will suffocate the roots and lead to root rot. You need the roots to be able to breath.
If you only have an all-purpose potting soil, you can mix in some chunky perlite, coco coir (a great peat alternative), and some orchid bark or coconut husks to help lighten it up. I keep most of these things on hand, but it’s often easier to just buy a bag of soil that comes pre-mixed with everything in it.
Want more philodendrons? Check out my post about 20 Philodendron Types With Photos!
Temperature & humidity
As with other tropicals that have adapted well to life as indoor plants, philodendron black cardinal enjoys temperatures anywhere in the 60s, 70s, and 80s Fahrenheit. It is not cold or frost hardy, so it needs to stay indoors if you’re somewhere that has fall and winter.
However, if you have the plant outdoors for the spring and summer, it is totally fine if the evening temperatures drop down into the 50s here and there. Growth will likely slow if you make it a habit, but the plant will be fine.
As for humidity—the higher, the better. But the plant’s thick, leathery leaves also do quite well in average indoor humidity levels. I currently have mine in my sunroom grouped with other plants, which helps to bump ambient humidity levels a bit higher.
However, I’m also planning to run a humidifier in this room during the day through the winter. I hate humidifiers, so I don’t bother with them in the spring and summer. But it gets SO dry here in the winter, so I’m committing this year.
How fast does philodendron black cardinal grow?
Philodendron black cardinal is a slow grower. It can grow up to about 36 inches tall and about half as wide as it is tall. Because black cardinal isn’t a particularly fast grower, you probably won’t need to repot it every spring.
Instead, monitor the pot’s drainage holes for roots poking out. When they start poking out of either the top or bottom of the pot, it’s time to give the plant a bit more space. Size up about an inch and use some fresh well-draining soil when it’s time for a new home.
Is philodendron black cardinal a climber?
It has a very compact, self-heading growth pattern that means it does not require staking or a pole. That said, I have a little bamboo stake in mine to help it grow straight. I find it is a little floppy if I don’t.
I just have the plant loosely tied to the stake using a piece of sticky plant tape. It’s mostly in there for a bit of moral support 🙂
Like darker plants? Check out my Raven ZZ Plant Care & Propagation guide, my Scindapsus Treubii Dark Form Care post, and my Sansevieria Black Coral Care guide!
I have not traditionally used a lot of fertilizers for my houseplants. I use a high-quality potting soil when I repot plants in the spring, and that generally has some sort of slow-release fertilizer in it.
However, this year I started using Liqui-Dirt concentrated plant food. It’s super easy; you just add it to your watering can. I use this roughly once a month in the spring and summer. It’s not cheap, but one package lasts me an entire growing season since you need so little.
How to propagate a philodendron black cardinal
Philodendron black cardinal is relatively easy to propagate—it’s taking a good cutting that’s the hard part. That’s because it’s a self-heading, compact variety. It doesn’t have a long, climbing exposed stem you can cut from.
Propagating a black cardinal from a cutting
It’s not impossible, though. Take a look at my plant below. I could easily take a cutting from the top of the plant and grab that little root with it. But all you need is a cutting with a few leaves and a few nodes.
The nodes are growth points, or the area where the leaf sprouts from the stem. So you could take a cutting with 4-5 leaves on it and remove the bottom set of two leaves to expose the growth points.
Let the cutting rest overnight and then pop it in water. Refresh the water weekly and watch the roots develop. Once they are several inches long, you can transplant the cutting to soil.
You’ll want to keep the soil relatively moist while the water roots are converting to soil roots. Once you can pull on the plant and are met with resistance, you know the plant has rooted. Back off watering and care for the plant as normal.
You could also choose to root the cutting in damp moss and perlite or LECA. Both are great options. You could also skip rooting all together and plant the cutting directly in soil…but I hate doing that since I can’t monitor the roots that way!
Propagating a black cardinal through division
My black cardinal has only one plant growing in its pot. However, if you have more than one plant in the pot, you can divide them and pot them up separately.
This is as easy as removing the plants from the pot and gently brushing away the soil. When you do that, you’ll be able to see where the two plants emerge from. Separate them, making sure to take roots along with you.
Use fresh well-draining potting soil and smaller pots to pot these up separately. Smaller pots are a good idea because the root systems are now separate, meaning they are smaller.
Pests & other issues
Philodendron black cardinal is relatively resistant to pests. However, it’s vulnerable to the normal lineup of houseplant pests: fungus gnats, mealybugs, aphids, and scale.
If you notice tiny gnats flying around your plant’s soil line, it’s fungus gnats. While they won’t necessarily hurt your plant, the cause of them might: overwatering. Fungus gnats lay eggs in the top few inches of soil, and they love moisture.
Generally you can kill them off by letting the plant’s soil dry out before watering it again. However, if you’ve got a particularly bad infestation, check out my post about fungus gnats and how to get rid of them.
Aphids and scale feed on plants and generally leave behind a clear or brown sticky residue on or around the plant. Treat them with an over-the-counter insecticide that has the pest you’re targeting listed on the bottle.
And mealybugs—I have a post all about how to get rid of mealybugs. Do you see cotton-looking passes on your plant? Especially on the undersides of leaves or where the leaves meet the stems?
Those are mealybug nests! If you have a light infestation, you can pick them off with a Q-tip soaked in alcohol. If you need bigger reinforcements, check out my post linked above.