The tropical Split Leaf philodendron plant is often called, mixed up with, and interchanged with a Monstera deliciosa plant or Swiss cheese plant. Although both plants are in the same large Araceae family, have the same care requirements, and grow in a similar manner, they are not the same plant. The Split Leaf philodendron plant is a close relative of the pothos plant. The Monstera deliciosa, found in Mexico and often grown for its “breadfruit,” is a close relative of the Peace Lily plant (Spathiphyllum).
A Split Leaf philodendron, sometimes called a Lacy Tree philodendron or Horsehead philodendron, is a very large, popular, easy- care houseplant. These plants have big, glossy, leathery, heart- shaped leaves that, as the plant matures, split from the leaf edge to the center vein. The slits in the leaves of a Split Leaf philodendron are called cuts. When young, a Split Leaf philodendron plant has strong upright stems. As the plant grows larger and the leaves get bigger and heavier, the philodendron stems start to droop down until they are almost horizontal to the ground. A Split Leaf philodendron grows rapidly indoors, especially if the humidity is high, and often has leaves that are as large as 3ft. long and 2ft. wide. When grown as a houseplant, it takes about 15–20 years for a Split Leaf philodendron plant to produce flowers. Eventually, an indoor Split leaf philodendron plant grows to be about twice as wide as it is tall and takes up quite a bit of space in your home or office.
Monstera deliciosa Swiss Cheese Plant Variegated Split Leaf Philodendron
The leaves, stems, and roots of a Split Leaf philodendron contain oxalic acid and the plant is considered very poisonous. Read more about common houseplants that are poisonous in Don’t Feed Me to Your Cat: A Guide to Poisonous Houseplants. If you want a big, tropical, low maintenance plant and have plenty of room, a Split Leaf philodendron plant is perfect.
Brown leaves and edges on a split leaf philodendron usually mean that the plant needs more water, especially in the warm weather; or more humidity, especially in the winter when the heat is on. Keep the soil a little moist but never soggy. To increase the humidity, you may have to put your plant on a tray of pebbles filled with water (be sure the plant sits on the pebbles and not in the water), use a humidifier near the plant, or group three or four plants together to increase the humidity.
Sounds like your split leaf philodendron is over watered. Reduce your water and move the plant to a brighter, warmer location so the soil has a chance to dry out faster.
Leaves are small and don’t develop splits, or cuts as they are sometimes called, occurs when the plant is not getting enough light. Move the plant closer to a window but avoid direct sun.
I think the long, brown stem-like things you are referring to on your split leaf philodendron are air roots. In nature, these air roots help support the very weak-stemmed split leaf philodendron. You can plant them in the soil to give the plant more stability or but cut them off if you find them too unattractive.
A split leaf philodendron likes to have plenty of room for its roots. Larger pots encourage larger leaves. If you want your split leaf philodendron to keep getting larger, repot annually. If you want to limit the size of your plant, stop repotting it.