Philodendron Melanoneuron (Complete Growing Guide!)

hand holding a small potted philodendron melanoneuron, a elongated heart-shaped philodendron with deep green ridges

The Philodendron Melanoneuron is an underrated and unusual tropical Philodendron.

Truth be told, we don’t think the Philodendron Melanoneuron is the most eye-catching Philodendron there is. But what it lacks in drama it makes up for in elegance.

We fell in love with the symmetrical, prominent ridges on its leaves…. and its pink roots! 🙂

Care-wise, the Philodendron Melanoneuron doesn’t ask for much. It loves a chunky potting mix and humidity >60%. Keep this plant away from direct light, but rotate every week for even growth. Being a natural climber, provide this Philodendron with a moss pole to grow to its ultimate height.

It also benefits from a gentle, urea-free fertilizer.

Let’s dive into the details!

Origins

This tropical plant has a native range between Colombia to Ecuador. There, it lives in the understory of the rainforest, so is accustomed to receiving filtered light.

Caring for your Philodendron Melanoneuron

Light

The key thing to remember for the Philodendron Melanoneuron is to avoid direct light, or risk sun-scorched leaves!

Instead, keep your plant near an East or West-facing window.

Avoid placing directly next to a bright, South-facing window, as this might be too harsh for your plant.

Water

Watering is a critical aspect of care for Philodendrons. Aim to keep the soil damp but not soggy. To accomplish this,

  • Check the top 2 inches (5cm) of soil with your fingers.
  • If the topsoil is dry, water your plant deeply, until excess water escapes from the drainage hole.
  • If the topsoil is still moist, don’t water.
  • Check the topsoil every couple of days.

You’ll notice that watering frequency naturally adjusts according to your plant’s needs, as you are checking to see if it needs watering rather than following a fixed schedule.

You’ll find that watering frequency is the highest in the summer and spring months, and reduces significantly deep in winter months.

close up topview of a philodendron melanoneuron with deep green ridges

Humidity

Being a tropical rainforest plant, your Philodendron Melanoneuron loves humidity. Aim for >60% humidity!

Humidity is important as it indirectly helps your plant carry out photosynthesis. Which explains why a lack of humidity can lead to slower growth!

High humidity levels keep your plant’s stomata (pores) open, allowing carbon dioxide, which is needed for photosynthesis, to be absorbed. If humidity is too low, plants close their stomata to prevent water from being lost by evaporation.

Of course, the ideal level of humidity depends on your plant and what it is used to in nature. For Melanoneurons, aim for >60%!

Temperature

This part of care is simple. Keep your Philodendron Melanoneuron between 70-90 degrees F (15 – 32 degrees C) for best growth. 🙂 Luckily, that’s most indoor temperatures.

Temperatures below 55 degrees F (13 degrees C) typically result in dropping leaves. Dropping leaves may also result from being placed in a windy spot, or too close to an air vent or drafty door.

While commonly kept as a houseplant, the Melanoneuron also can be grown outdoors in USDA hardiness zones 10b to 11. (If kept outdoors, just be extra sure that you don’t place your plant in direct sunlight, as light intensity is significantly higher outdoors!)

Flowering

While rare when kept indoors, your Philodendron Melanoneuron can bloom! It grows thick greenish-pink spathes, with a central spadix that is often partially hidden. Inflorescences grow in multiples, often 3-6 per axil.

Growth

Under optimal growth conditions, your Philodendron Melanoneuron grows pretty quickly. It can put out 1-2 leaves per month. If your Melanoneuron’s growth is slow, it’s usually due to insufficient light.

Relocate it to a brighter spot that receives plenty (at least 8 hours a day) of indirect light.

Since your plant is a natural climber, use a moss pole to support its climbing habit. Besides giving your plant a structure to climb on, moss poles encourage faster growth and bigger leaves.

(Check out our article on moss poles for find out more.)

Soil or Growing Medium

The Philodendron Melanoneuron HATES being in dense potting soil. In the wild, it doesn’t grow in soil… rather climbs on trees, with its roots in the air (aerial roots) or lodged in little crevices of shallow leaf litter. Never fully covered in the ground.

So you’ll want to choose a potting mix that is airy and well-draining.

This is the exact recipe we use and love:

Mix it all together and viola!

close up of the philodendron melanoneuron leaf with green ridges

Fertilizer

Apply a water-soluble, gentle (urea-free) liquid fertilizer once a month during the growing season. We are partial to Dyna-gro Grow, which we use for almost all our houseplants. It’s urea-free, nutritionally complete and works well for most foliage houseplants.

In the fall and winter, reduce fertilizing frequency to once every 8 weeks. Don’t overdo it!

In the case of fertilizer, less is more. 🙂

If you live in near the equator and therefore live in year-round warmth (without seasons), you can continue to fertilize your Philodendron Melanoneuron monthly. As long as you see your plant putting out new growth, there’s no need to cut back on fertilizing frequency.

Repotting

Repot your plant every 2 years, or when you see that your plant is root-bound, whichever is sooner. Spring is the best time to repot.

Here’s our step-by-step repotting guide.

Toxicity

As with many Aroids, the Philodendron Rugosum is considered toxic when ingested by animals and humans. This is due to insoluble calcium oxalate crystals contained in the stems and leaves.

Effects of ingestion include drooling, nausea, vomiting, gastrointestinal pains, and mouth burns.

close up of the pinkish roots of a philodendron melanoneuron

Propagation

Stem cuttings are an easy way to propagate an established Philodendron Melanoneuron. If you only recently brought your plant home, wait at least 8 months before trying to propagate.

When done right, propagation thru stem cuttings has a high success rate. And especially so when you choose a healthy, established stem with aerial roots!

Propagation through Stem Cuttings

Here’s how:

  1. First, gather all the items needed:
    • Sharp, sterilized garden shears. You can sterilize them by dipping them into 70% isopropyl solution;
    • a rooting hormone;
    • Potting mix (we recommend equal parts indoor potting soil, orchid bark, and pumice. Plus a handful of charcoal added in);
    • and a small pot with drainage holes.
  2. Identify a healthy length of stem that is around 4 inches (10cm) long. Make sure that this stem has a couple of leaves and at least two nodes! Even better if it has some aerial roots growing.
  3. Using sterilized garden shears, cut off the identified stem. Cut just below the node.
  4. Remove leaves, if any, from the bottom half of the stem cutting.
  5. Dip the cut end of the stem into a rooting hormone. This encourages roots to grow.
  6. Plant the stem cutting in a small pot filled with potting soil.
  7. Place in a warm spot with plenty of indirect light. If you have one, place a humidifier next to the new plant and set at 80%.
  8. Keep the potting soil lightly moist, but never waterlogged or soggy.
  9. In about 3-4 weeks, roots should emerge. You will know that roots have developed when you feel slight resistance when giving your plant a very gentle tug.
  10. Treat as you would any other Philodendron Melanoneuron. 🙂

Pruning

hand holding up a potted philodendron melanoneuron showing its green stems and green leaves

Common Pests and Diseases

Your Philodendron Melanoneuron is not particularly susceptible to pests or diseases. However, no plant is 100% immune.

If a problem arises, these are usually due to i) cross-infection of houseplant pests like spider mites or scale; or ii) fungal diseases that arise from an overwatered plant.

Regularly checking your houseplants for pests and adopting good watering practices honestly will save you from 90% of potential problems.

Root Rot

Root rot happens when your overwatered plant can’t breathe. Too much water crowds out air pockets within the soil, suffocating the roots, causing decay. Moisture-loving fungi eat away at the roots.

It’s so important to get into the habit of not watering your plant UNLESS the topsoil is dry. Having an airy potting mix with loads of chunky amendments like bark, pumice and charcoal is also really important, as it creates air pockets in the soil, and drains away excess water quickly.

Pests

Spider mites and scale are common houseplant pests. Both pests pierce your plant’s tissue and draw out its sugary sap, wounding your poor plant and depriving it of nutrients!

  • Being less than 1/50 inch (0.5mm) long, spider mites are hard to see without a microscope. However, fine webbing under the leaves and stems indicates the presence of spider mites. You may also observe faded and greying leaves, as spider mites suck out the chlorophyll.
  • Scale refers to over 7,000 species of insects, usually 1/16 – 1/8 inch (1.6mm – 3mm) long that appear in clusters. If you look closely, you’ll see a group of “bumps”. They have an oval, shell-like “bump” appearance, and come in a range of colors including orange, tan, and black.

It’s essential to detect these pests early, as they reproduce very quickly.

We use either Bonide Insecticidal Soap or neem oil to eradicate these pests. If caught early, both are very effective ways to stop these bugs from killing your plant. Apply per the instructions.

Troubleshooting

Yellow leaves

Yellow leaves alongside a droopy or wilted-looking plant is commonly due to overwatering. So make sure that you are watering your plant correctly.

Curling leaves

Curling leaves typically mean your Philodendron Melanoneuron is underwatered. Check the soil moisture with your fingers to confirm.

Brown leaf tips

In a Philodendron Melanoneuron, brown leaf tips indicate a lack of moisture â€“ either in the form of underwatering, or a lack of humidity (which is a measure of moisture levels in the air). Sometimes it can be an indication of both!

Adjust your watering practices accordingly, and use a humidifier to fight dry conditions.

Similar Plants and Varieties

Wrapping Up

This easy-to-care-for Philodendron Melanoneuron has an understated beauty thanks to its symmetrical ridges. If you’re lucky enough to get your hands on this unusual Melanoneuron, make sure you:

  • Provide it bright, indirect light.
  • Water only when the top 2 inches (5cm) of soil is dry, but check the soil moisture every few days so that you don’t accidentally let it dry out through its pot.
  • Give it adequate humidity, >60%.
  • Keep it in moderate temperatures – between 70-90 degrees F (15 – 32 degrees C)
  • Use a chunky well-draining mix. We like equal parts indoor potting soil, pumice and orchid bark; plus an added handful of charcoal.
  • Lightly fertilize monthly during the growing season and every 8 weeks in fall and winter, at half strength.

Deborah is a plant enthusiast and founder of Gardening Collective.