How to Grow and Care for Philodendron Mexicanum

The Philodendron Mexicanum is a houseplant known for its unique foliage. Its leaves have a slender, arrow-like shape that develops into a tri-lobed form as the plant matures. The tops of the leaves are a glossy, deep green, which contrasts with their maroon or reddish undersides. This vining species is a natural climber, a trait that influences its development indoors.

Philodendron Mexicanum Care

Light

Proper lighting is important for the health of Philodendron Mexicanum. The plant flourishes in bright, indirect sunlight, so an ideal placement is near a window where the sun’s rays are filtered to prevent scorching the leaves. Insufficient light results in slower growth and a “leggy” appearance where the space between leaves increases. Optimal lighting encourages more vigorous growth.

Soil

Philodendron Mexicanum requires a loose, well-draining potting medium high in organic matter. Standard potting soil is too dense and can retain excess water, leading to root rot. A good mix includes ingredients like peat moss, perlite, and orchid bark. This combination provides aeration and moisture retention without becoming waterlogged.

Water

Water this philodendron based on soil moisture, not a rigid schedule. It is best to water when the top 2-3 inches of soil feel dry. Water thoroughly until it flows from the drainage holes, then discard any excess from the saucer. Never allow the plant to sit in standing water, as this can lead to root rot.

Temperature and Humidity

This plant originates from tropical regions and prefers warm, humid conditions between 65-80°F (18-27°C). Protect it from cold drafts and sudden temperature drops by placing it away from drafty windows or air conditioning vents. While it tolerates average indoor humidity, it benefits from higher levels. You can increase ambient moisture by misting the leaves, using a pebble tray, or placing a humidifier nearby.

Fertilizer

To support its growth, Philodendron Mexicanum benefits from regular feeding during the spring and summer. Use a balanced, water-soluble liquid fertilizer diluted to half-strength about once a month. Reduce or stop fertilizing entirely during the fall and winter when the plant’s growth naturally slows.

Encouraging Mature Growth

To encourage the development of its mature foliage, it is beneficial to replicate this plant’s natural climbing habit. Providing a support structure, such as a moss pole or trellis, allows the plant to anchor its aerial roots and grow vertically. This act of climbing triggers the plant to produce larger, more defined leaves.

As the plant climbs, its leaves undergo a transformation from the juvenile arrow shape to the mature, larger tri-lobed structure. Without a support, the plant may still trail, but its leaves are less likely to reach their full size and characteristic shape.

How to Propagate Philodendron Mexicanum

This philodendron is propagated through stem cuttings. First, select a healthy vine and use clean, sharp shears to make a cut just below a node, which is the small bump on the stem where leaves and aerial roots emerge. Ensure each cutting has at least one leaf and a node, as new roots will develop from this point.

You can root the cutting in a jar of water or directly in soil. For water rooting, submerge the node and change the water when it becomes cloudy. Once roots are about an inch long, plant the cutting in soil. Alternatively, plant the cutting directly into a pot with a moist, well-draining potting mix. Keep the new cutting in a warm spot with bright, indirect light and consistently moist soil until it is established.

Troubleshooting Common Problems

You might encounter some common issues with your plant.

• Yellowing leaves: This is often a sign of improper soil moisture. It can be caused by overwatering or, less commonly, severe underwatering where the plant sheds old leaves to conserve water.
• Brown, crispy leaf edges: This points to a lack of humidity or inconsistent watering.
• Leggy growth: Long stretches of bare stem between the leaves indicate insufficient light. Move the plant to a location with brighter, indirect light to resolve this.
• Pests: Common houseplant pests like spider mites and mealybugs can affect the plant. These can be managed by wiping the leaves and treating them with insecticidal soap or neem oil.

Toxicity Information

Like all plants in the Araceae family, Philodendron Mexicanum is toxic to pets and humans if ingested. All parts of the plant contain insoluble calcium oxalate crystals. If chewed or swallowed, these microscopic crystals can penetrate the soft tissues of the mouth and throat.

This causes immediate irritation, pain, a burning sensation, swelling of the lips and tongue, excessive drooling, and vomiting. To ensure safety, the plant should be placed out of reach of cats, dogs, and small children.