Two philodendrons that have become increasingly popular over the last few years are the philodendron black knight and black cardinal.
While the two houseplants belong to different species, they both fall under the same genus, philodendron, which belongs to the family Araceae.
This shared heritage gives the two indoor plants several similarities that can be confusing when deciding which one to choose for your home. However, they are different plants with significant differences that can make one better suited to your needs than the other.
This philodendron black knight vs black cardinal article discusses the similarities and differences between these two philodendrons. Read along.
What is Philodendron Black Knight?
Philodendron black knight is a tropical plant with dark burgundy leaves. The leaves are heart-shaped and nearly black, which explains the black in its name.
This philodendron is available in climbing and non-climbing varieties that grow into enormous plants. If you want to have one of these non-climbing black knight varieties, ensure you have a large enough space to accommodate them.
Being a tropical plant, philodendron black knight will do well in bright indirect sunlight. When grown indoors, you can place the philodendron near an east or south-facing window and use sheer curtains to block the sun’s rays from hitting the plant directly.
The plant’s native tropical habitat has also conditioned it to prefer well-drained soil, high humidity, and regular watering without keeping the roots in wet soil.
So you need to allow the soil’s top two centimeters to dry out before watering the plant as part of its care routine.
Since this philodendron produces aerial roots, you can always support it with a sturdy totem to encourage upright growth.
What is Philodendron Black Cardinal?
Philodendron black cardinal is a low-growing philodendron plant with dark green, nearly black leaves with an apparent gloss.
The glossy blackish green and bronze leaves are oval shaped, which sets them apart from the deeply lobbed leaves of its close cousin—the black knight.
The black cardinal is a hybrid philodendron that is naturally low-growing, another characteristic that differentiates it from the black knight.
This perennial shrub has a clumping tendency, which, coupled with its low growth, may mean you don’t have to support it to encourage upward growth. You can describe this plant as self-heading; it does not sprawl or crawl the way vining philodendrons do.
The newly emerged leaves are bronze or light orange. However, they take on a deeper, dark green hue with age.
This means you’ll find the darkest leaves on the lowest parts of your philodendron black cardinal. The leaves are also much brighter and glossy when they emerge but become dull as they age and fall down the levels to the lower parts of the plant.
The black cardinal is a flowering plant. You can expect its flowers to emerge anytime during the warm months of the year.
Philodendron Black Knight Vs Black Cardinal Side by Side
Both back knight and black cardinal are philodendrons that have gained increasing popularity in recent times. They are some of the most common houseplants in many regions and share numerous similarities.
Still, these plants have some notable differences that play a key part when choosing between them.
Philodendron Black Knight Vs Black Cardinal: Differences
Philodendron back knight and black cardinal may look similar on the surface, but they have various dissimilarities. Some of these differences are obvious and become noticeable immediately you look at the plant, while others are more subtle.
This section looks at the main differences between these two popular philodendrons to help you tell them apart more easily.
1. Leaf shape and color
The leaf shape is one of the most obvious differences between these two philodendrons.
On the one hand, the philodendron black knight has a deeply lobed, heart-shaped leaf with a glossy surface texture. On the other hand, philodendron black cardinal leaves are oval-shaped, making them noticeably different from the black knight leaves.
Also, the black knight leaves are dark burgundy or green, with the color depth making the leaves appear almost black. This color remains widely consistent as the leaf ages.
In contrast, the philodendron black cardinal has dark green leaves that are typically light orange or bronze when they emerge.
As the leaf ages, the bronze or light orange color gradually disappears as the leaf takes on a deeper, dark green hue.
Like the philodendron black knight, the mature leaves of the black cardinal are dark green, almost black.
However, you can easily tell the two plants apart because the black cardinal will have lighter colored leaves toward the top with darker colored leaves, the darkest leaves on the lower parts of the plant.
The black knight leaves should have the same dark green color across the entire plant.
2. Leaf texture
While mature philodendron black cardinal leaves are dark green like those of the black knight, their texture is different.
The mature black cardinal leaves tend to be dull with a matte feel, even though new ones emerge with a shiny gloss. The leaves lose this glossy texture with age.
Philodendron black knight, on the other hand, has leaves that tend to appear glossy regardless of age.
3. Temperature preference
Since philodendron black knight and black cardinal are tropical plants, they prefer relatively higher temperatures for this optimal growth.
Ideally, various philodendron species will do well in temperatures above 55 degrees Fahrenheit (13°C), with anything below that level likely to kill them.
However, the specific temperature tolerance varies significantly among various philodendron species. That is the case with the black knight and black cardinal varieties.
Philodendron black knight requires temperatures ranging between 55 and 70 degrees Fahrenheit.
Philodendron black cardinal, on the other hand, prefers slightly warmer climates with indoor temperatures ranging from 65 to 80 degrees Fahrenheit.
Neither plant likes extreme temperature fluctuations and will likely not survive prolonged exposure to cold drafts or temperatures below 55 degrees Fahrenheit.
So if you have either the black knight or black cardinal, ensure you avoid placing it near an air-conditioning vent or radiator.
4. Leaf size
A grown philodendron black knight leaf measures about 10 inches long, with smaller ones measuring approximately 7 inches long.
In comparison, the philodendron black cardinal has a slightly larger leaf size, measuring anything from 8 to 12 inches long.
While this difference in leaf size may be minimal, it becomes more noticeable when considered alongside the leaf shape and color.
5. Pant height and spread
The two philodendrons have a significant height difference, which can make it easier to tell them apart.
The black cardinal is a smaller plant that grows to a maximum height of approximately 3 feet. It must get optimal growth conditions to attain this height. Otherwise, it will be much shorter.
In contrast, the black knight plant is much taller, reaching about 9.8 feet when fully grown. The taller philodendron black knight also grows faster than the shorter black cardinal plant.
Like all plant species, your philodendron black knight or black cardinal will experience stunted growth if it does not get the proper care and maintenance. So ensure you follow the recommended maintenance practices to see your plant reach its optimum height and spread.
Key among these care requirements are bright indirect sunlight, regular watering, and fertilization.
With proper care, your philodendron black knight can spread to a width of 1 to 1.6 feet. The philodendron black cardinal has a nearly similar measurement, with its spread ranging between 1 and 1.5 feet wide.
Philodendron black knight will likely require repotting sooner than black cardinal due to its faster growth. The black cardinal grows slower than philodendron black knights.
If you have a philodendron black knight, you will need to repot it annually to avoid being root bound. The plant grows pretty fast and can outgrow its pot in a year or less.
Since philodendron black cardinal grows relatively slowly, you can repot it every two to three years.
You can tell it is time to repot your black cardinal when its roots start emerging out of the pot’s drainage holes.
When repotting either plant, consider doing it in early spring. Choose a vessel that is at least one size larger than the initial pot. Also, ensure the new pot has enough drainage holes.
If it doesn’t, consider creating them before transferring the plant into it.
Philodendron Black Knight Vs Black Cardinal: Similarities
Since both plants belong to the same philodendron genus, they have many shared characteristics and requirements for growth.
Both plants are relatively low-maintenance, with similar growth requirements for lighting, soil type, and humidity preference. Here is a detailed rundown of the shared aspects between these two tropical plants.
i. Watering preference
Both philodendron black knight and black cardinal do not like having their roots in wet soil. So avoid overwatering them.
To ensure you give your plant just the right amount of water, we recommend testing the nutrient rich soil with your finger to check if at least 2 centimeters of the top layer is completely dry. If it is, you can proceed to water the plant. Otherwise, wait a little longer.
ii. Soil type preference
Both philodendron black cardinal and black knight prefer chunky soil with good moisture retention. Such is adequately aerated and well-draining soil. So it allows the roots to breathe well and not stay in a soggy environment for long.
The moist soil must also be nutrient-rich, with high organic content to feed and nourish the plant. Such soil is often loaded with peat moss and other organic ingredients.
iii. Light requirements
Since these are tropical plants, they thrive in bright indirect sunlight. You can satisfy such conditions for the plant by placing them near an east or south-facing window and using sheer curtains designed for plants to filter the bright light for them.
Since black knight is more tolerant to partial shade than black cardinal, you can place it in a window that receives less sunlight.
iv. Humidity requirement
Both philodendron black cardinal and black knight thrive in high-humidity environments that mimic the warm conditions in their native habitats.
Consider keeping the indoor humidity around these plants between 60 and 70 percent. Since the plants have large leaves, so they need such humid conditions to prevent dehydration through excessive transpiration.
How to increase humidity around the plant
- Use a humidifier
- Place a pebble tray under the plant
- Mist the plant regularly
- Group multiple plants together to facilitate natural transpiration.
- Fertilizer preference
Neither of these two philodendrons is a heavy feeder, but they will become healthier if you regularly feed them with a slow-release fertilizer. Consider applying a balanced NPK 20-20-20 fertilizer to the soil at the beginning of the plants’ growing season.
Ensure you dilute the fertilizer to half-strength to avoid the risk of fertilizer burn.
v. Propagating philodendron black knight vs black cardinal
To propagate your philodendron, you can use air layering or stem cuttings in the spring or summer. These two options are available for the climbing philodendrons.
However, you can use a sterilized instrument to snip a shoot near the base of the plant. This can serve as a stem cutting for propagating the houseplant.
How to propagate philodendron black knight with a stem cutting
- Start by snipping a stem about four inches long, right below a leaf node. Ensure the cutting has a few leaf nodes where growth will occur.
- Place the cutting in a glass of filtered water or rainwater to develop roots. Ensure you change the water in your rooting medium every three to four days until the cutting develops roots.
- Transfer the stem cutting to a vessel with the correct potting mix once the roots have developed and reached about an inch long.
- Ensure the pot has enough draining holes or create them if it does not have enough.
- Place the little plant in a humid and warm space with lots of indirect sunlight.
Philodendron Black Knight Vs Black Cardinal: FAQs
What is a black knight philodendron?
Black knight philodendron is an aroid plant with dark burgundy leaves. The potted plant’s leaves are heart-shaped and deeply lobed. This philodendron is available in climbing and non-climbing varieties that grow into immense plants.
What is the difference between the philodendron black cardinal and the red Congo?
Philodendron black cardinal has rounder, larger leaves and darker foliage, which sets it apart from red Congo and other similar red cultivars. Notice that the black cardinal will have darker, almost black leaves on the lower parts of its stem.
Is philodendron black cardinal rare?
Regular philodendron black cardinal is not rare. However, the variegated variant of this cultivar is pretty rare. However, it is one of the most beautiful variegated plants under the philodendron genus.
Related post: Philodendron Pedatum Vs Florida Ghost
Black knight and black cardinal philodendrons have some similarities, but their differences are clearly noticeable. While the black knight has deeply lobed, heart-shaped leaves, the black cardinal leaves are oval-shaped.
Also, the black knight leaves are dark burgundy and the same color across the entire plant, while the black cardinal has blackish green leaves that are bronze or light orange when they emerge. As such, the black cardinal will have leaves with different colors at each point as opposed to the black knight.
We hope this in-depth comparison helps simplify things for you. Share your thoughts with us in the comments.