Philodendron selloum also called as Philodendron bipinnatifidum, Lacy tree philodendron, Selloum, Horsehead philodendron and its scientific name Thaumatophyllum bipinnatifidum, is a species of the genus Thaumatophyllum. This species was described by Sakur., Calazans & Mayo in 2018. When given enough room to spread, this plant makes a handsome foundation or specimen planting and can also be used in large containers where it looks especially attractive at poolside.
I. Appearance and Characteristics
Thaumatophyllum bipinnatifidum (common names: split-leaf philodendron, lacy tree philodendron, selloum, horsehead philodendron, guaimbé) is a plant in the genus Thaumatophyllum, in the family Araceae. Previously it was classified in the genus Philodendron within subgenus Meconostigma. The commonly used names Philodendron bipinnatifidum and Philodendron selloanum are synonyms. This plant is native to South America, namely to Brazil, Bolivia, Argentina, and Paraguay, but is also cultivated as a landscape plant in tropical, subtropical and warm temperate climates.
The common name “split-leaf philodendron” is also used for Monstera deliciosa.
- Growth habitat
Thaumatophyllum bipinnatifidum is a tropical plant that is usually grown in full sun, but can tolerate and adapt to deep shade. It grows best in rich, moisture-retentive soil that can be slightly alkaline. However, it cannot tolerate high salt concentration in soil. It is capable of supporting itself at massive heights by producing tree-like bases. However, it will exhibit epiphytic characteristics if given the opportunity to attach itself to a nearby supporting tree and climb upon it.
The trunk of this plant can send down many strong aerial roots that not only give support to the overall plant mass, but also serve to absorb water and nutrients from the soil. This plant is greatly known for its ease in covering a land mass, and typically spread out its tree-like trunk from anywhere between eight and ten feet. Alternatively, if grown in cooler climates with at least some freezing winter weather, its entire aboveground structures will die back completely at a hard frost and then sprout back from the roots the following spring.
- Distinguishing features
The leaves are simple, large, deeply lobed, and are usually drooping. These can grow up to 1.5 meters long, and are attached to long, smooth petioles. They are a deep green color, and since these plants are grown in the tropics, there is no apparent color change that correlates with the fall season. The trunk of T. bipinnatifidum is relatively thick and woody with characteristic “eye-drop” leaf scars. Approximately 15–20 years is required for T. bipinnatifidum to grow to an appropriate size and produce flowers in an indoor environment where space is limited. The small, petalless flowers are on a spadix that is enclosed within a spathe. They are usually white or inflorescent.
- Reproduction
The reproductive organ consists of a spadix grown at the center of a reproductive layer called the spathe. The spathe is sometimes mistaken to be a flower, but it is really a modified leaf that serves to protect the spadix. The spadix is divided into three sections: fertile male flowers at the tip, sterile male flowers at the center, and fertile female flowers toward the end of the flower chamber. The sterile male flowers in the midsection serve to prevent self-fertilization and to produce heat. Pollination is done by a Cyclocephala beetle species. The sterile male flowers produce and maintain a constant temperature that is 34 °C (93.2F) above that of the environment during the two days the entire flower structure is open by burning stored fatty tissue – comparable to the metabolic output of a small cat. T. bipinnatifidum metabolizes fat, instead of carbohydrate, to fuel this process.
This feature indicates a possible evolutionary convergence where this plant species and animal species derived similar mechanisms to utilize fat reserves for energy consumption. The main reason for raising and maintaining the flower’s temperature is for volatilizing and dispersing insect attracting odors. The constant high heat production increases the distance that the scent can be picked up by the beetle, and increases the probability of pollination. Additionally, the heat creates a hospitable climate that helps to stimulate beetle activity once it is inside the flower and induce them to mate (this being a favorable temperature for them to do so). This will also increase the probability of pollination as they linger inside it.
T. bipinnatifidum sap may cause skin irritation. Chewing and/or ingesting parts of the plant may result in severe swelling and compromised respiratory functions.
II. How to Grow and Care
Sunlight
The tree philodendron does best in locations that receive dappled shade or medium to bright indirect light. Indoors, sunny windows filtered with a thin curtain or window blinds are ideal spots for a tree philodendron. As with most varieties of philodendron, the tree philodendron does not do well in low-light conditions. Lack of light can lead to stunted or leggy growth. The leaves of a tree philodendron reach towards the closest light source, so it is best to regularly rotate the plant to maintain symmetrical growth.
Temperature and Humidity
The tree philodendron grows well in warm, humid environments. When grown indoors, average household temperature and humidity levels are usually sufficient for this tropical plant if it is not placed too close to a heating vent or drafty window. If you notice that the leaves of your plant are yellowing or developing crispy edges, this could be an indication that it needs more humidity and could benefit from a humidifier or pebble tray filled with water. Outdoors, the tree philodendron is cold hardy in USDA cold hardiness zones 9a through 11b.
Watering
Encourage healthy growth by keeping the soil moist in your plant. By using distilled water, you can give your philodendron bipinnatifidum access to the cleanest and healthiest options. This is good if you are keeping a new growth plant inside.
However, it is possible to overwater the philodendron bipinnatifidum, so make sure to keep the soil moist and have good drainage in the soil. You will want to cut back a little with the watering to once or twice a week during the growing season, even in hardy zones. They can tolerate drought more than other plants, so this may be a good plant option if your area has that possibility.
Soil
This member of the aroid family prefers soil that is moist but well-draining and high in organic matter. The tree philodendron doesn’t tolerate acidic or salty soil. To create your own growing medium, use a mixture of one part compost to make the soil more alkaline, one part perlite for drainage, and one part orchid bark or coco coir. Peat moss is too acidic.
Fertilizing
Use a balanced fertilizer once a month throughout the growing season to encourage strong, healthy growth. To avoid fertilizer burn, stop fertilizing in the fall and winter months when the plant enters dormancy.
Pruning
Use sharp pruners or scissors to control the size and shape of the plant. You can remove entire leaves by cutting them off at the base of the leaf stem. You can also remove the lower leaves if you want to reveal the plant’s stem. Always wear gloves when pruning and wash your hands and tools when finished. You don’t want to get the sap in your eyes or mouth.
Propagation
The tree philodendron can be propagated through stem cuttings. Because these plants grow so large, trimming the stems might be necessary at some point to contain the size of the plant. Instead of throwing these cuttings into the trash, you can propagate them to create new plants.
To take a cutting, make a clean cut below a node on the stem. Each cutting should have 2-3 leaves and a couple of nodes on the stem. Place the fresh cutting in water and put it in a location that receives bright, indirect light. Change the water every week to keep it fresh. After a couple of weeks, you should begin to see small roots forming. When the roots are between one to two inches long, move the cutting water into the potting medium.
Repoting
After the growing season, it is time to take your new plant and move to a new pot. The aerial roots in your plant should be able to gather the nutrients they need and prepare for the changing weather.
If you keep your philodendron bipinnatifidum inside, you need to make sure that you change the pots every six months until it reaches maturity. This keeps the soil from getting too acidic and gives a growing medium to the indoor plant. Once it reaches maturity, you will want to make sure you are repotting your plant annually to ensure the soil creates aerial roots.
Pests and Diseases
These tropical plants are susceptible to a few common pests such as spider mites, fungus gnats, aphids, and mealybugs. Regularly inspecting the leaves for signs of pests is the best way to catch infestations early and eradicate them quickly.
Tree philodendrons are also susceptible to root rot, which occurs as a result of improper watering or compacted soil. Mushy stems and brown, dying leaves are both signs of root rot which can kill a plant quickly. If you catch root rot early enough, you might be able to save the plant by cutting off the rotted parts and propagating the remaining stem to grow a new root system.