Philodendron Rojo Congo Care (Red Congo) – Best Kept Secrets

The philodendron rojo congo is one of those rare philodendrons that is feverishly collected for its glossy leaves that unfurl to reveal a striking red color. When the leaves first appear, they can come in a burgundy light red or even a much darker orange, before deeping to that classic deep green as it’s exposed to more light. There are just a few things to keep in mind when looking at philodendron rojo congo care.

Note: The philodendron rojo congo is different to the philodendron imperial red despite looking very similar. Whilst both plants were bred specifically for the commercial market, the rojo congo is generally larger in its juvenile form, produces darker red leaves and grows quicker even when both are placed in optimal growing environments. 

Philodendron Rojo Congo Brief History & Origin

The philodendron rojo congo is incredibly new in terms of plant age and was never discovered. That sounds odd for a plant, but it’s because it’s a hybrid variety that was developed in the 1990’s by cross breeding a philodendron imperial red with a philodendron tatei.  It’s grown or rather harvested from nurseries in South America and Florida, though escapes have been found growing natively in the Philippines, small regions of South Africa and Australia, all introduced by man.

Is the Rojo Congo a Climbing or Self Heading Variety?

Here’s where it gets interesting. Despite what many believe, the rojo congo is a climbing variety, though this mutation is stronger in some specimens than others! It’s epiphytic meaning it loves to grow on and up trees. It looks like it will be a self-header (meaning it can support its own weight as it matures), but in some specimens it can be a climber. This is why you will see many plant blogs and nurseries stating one or the other. Neither are wrong.

Philodendron Rojo Congo Care

Soil

Like most philodendron varieties, the philodendron rojo congo loves a lightweight, airy and fast draining mix that includes rich organic matter. 

A mix of coco coir, perlite, worm castings, orchid bark, pumice and activated charcoal provides the perfect growing environment.

I love and use this mix for my philodendrons:

  • 40% coco coir
  • 15% orchid bark
  • 15% perlite
  • 10% worm castings
  • 10% pumice
  • 10% activated charcoal

The key with a potting mix is to make sure it contains elements that are fast draining as well as moisture retaining. It might sound counterintuitive but too much of one or the other can lead to chronic dehydration or waterlogged soil. Neither are a great growing environment for a rojo congo, or any philo for that matter.

The Science Behind this Mix

  • Coco coir (instead of soil) – fast draining, neutral in pH, yet can hold moisture too, very easy growing medium
  • Perlite – a glass pearl of volcanic rock, porous structure, low water retention, aids in drainage and holds nutrients
  • Orchid Bark – an epiphyte’s FAVORITE soil amendment, it becomes a hotspot for positive microbes, root attachment and chunkiness allows for extra drainage
  • Worm castings – organic fertilizer (literally worm poo), has a full nutrient palette
  • Activated charcoal – prevents build up of soil impurities, stops mould and neutralizes pH of soil
  • Pumice – another drainage element

This mix is the perfect blend, creating an airy woody substrate for epiphytes or hemi-epiphytes.

Light

The philodendron rojo congo needs lots of bright, indirect light to produce those large, wide and textured leaves. The more light you give it, the faster and wider it will grow. You’ll also see an increase in variegation if kept in a brighter location. Don’t be afraid to put it in a location that receives some cool direct morning sunlight either (emphasis on cool morning sun). Despite what many guides tell you, keeping philos in strictly indirect light is not a hard and fast rule. Direct morning sun can do your plant a whole lot of good. Problems only arise when the plant is kept in direct sun all day, where leaves can scorch.

Watering

A result of being crossed with two tropical plants, it probably comes at no surprise that the philodendron rojo congo loves evenly moist, well drained soil. The key here is well drained and not waterlogged or boggy. There’s no set schedule I recommend you keep e.g once a week – this is why lots of plants die unfortunately. It’s better to water based on what you can see is happening with your plant rather than a strict rule. 

Generally, you’re advised to water this plant when the top inch of soil is dry to touch, but again, this isn’t foolproof. Neither is using a soil moisture meter. 

Related: Soil Moisture Meters: Why You Should Never Use One (+What to Do Instead)

How to Tell When Your Plant Needs Watering

What I do and recommend is to use a bamboo chopstick, dig it into the soil, a good few inches deep, and observe what you notice. 

  • Wet soil will cling to the chopstick and possibly make the stick a darker shade
  • Moist soil will be soft in texture (you’ll easily be able to push the stick through)
  • Dry soil will be tough, brittle and compacted and won’t change the color of the stick

Or, you can use the good ol’ knuckle test. Stick your finger into the potting mix. If it is moist at the first or second knuckle, you can hold back on watering. If it is dry, your plant needs a good drink.

Always make sure to check the color of the soil and texture too. If the mix is really dark, it’s likely it doesn’t need any more water. If the soil is hard and compacted, it’s become super dry and might need changing.

Myth Buster: Indoor tropical plants can handle the exact same amount of water as they get in the rainforest. 

A. You’d think this to be true, but not quite. Whilst rainforest dwellers do love water and need it to carry out many processes including transpiration and photosynthesis, tropical plants indoors have nowhere near the same amount of drainage that their outdoor counterparts do. 

Rainforests maintain high base temperatures all year round and have a fog or dewy mist that works to increase humidity and evaporation levels, effectively wicking away excess water.

Humidity

Philodendron rojo conjo’s love humidity, and will reward you with larger leaves if kept in an environment with a humidity of 70% or higher, BUT maintaining a level of between 45%-50% will still result in good growth. If in winter months you notice the humidity level dropping too low, you can invest in a small humidifier to add some extra moisture into the air. You might also want to group your plants together so they can share ‘humidity’ resources via transpiration. Grouping creates a little mini biome in your home – cool right?

Temperature

As with most philodendrons, the Philodendron rojo congo can handle a wide range of temperatures, though it will love you more if it’s a little on the warmer side. The ideal growth range lands between 68°F to 78°F (20°C to 26°C), though they can handle as low as 59°F (15°C). Anything less than 54°F (12°C) and you’re likely to see severely stunted growth, wilting and a loss of that gorgeous deep green coloring.

Fertilizer

Unlike their outdoor friends, houseplants have no natural way of obtaining nutrients naturally once they’ve used up all the nutrients in their potting mix. This is why houseplants need regular fertilizing with a nutrient rich solution!

Best Fertilizer for Philodendron Rojo Congo

There are lots of options available to you on the market, including an all-purpose houseplant fertilizer, but I love and swear by dyna gro (7-9-5 NPK formula). It contains all 16 macro and micronutrients your plant needs to not just survive, but thrive.

It also comes with a ‘no-burn guarantee’ – it’s urea free and low in heavy nitrogen salts which over time alter the pH level of the soil and lead to root burn.

How to Fertilize Your Philodendron Rojo Congo

I used to fertilize my plants once a month like many nursery guides say to do but it seemed completely unnatural to me knowing how plants ‘feed’ in the wild!

In nature, plants receive a steady stream of nutrients from decaying matter over days – they don’t take one big gulp a month. 

For this reason, I fertilize my philos with a very diluted solution every time they get watered. You’ll sometimes hear this referred to as maintenance feeding. 

I dilute 1/4 teaspoon of dyna gro with 1 gallon of water (4.5 litres) and water my plant with this solution every time in spring and summer (when the plant is showing signs of needing to be watered).

Will this Burn my Plant?

It’s diluted to half and then half again so it’s very unlikely to burn the plant.

I also cut back both on waterings and feedings in autumn, and stop fertilizing completely in the winter months to prevent oversaturation during the more dormant part of their growth cycle.

Growth – What Can I Expect?

The rojo congo is a very wide bodied plant, peeking at 1m in width and up to 3m in height. In the wild, its hybridized form never grows compact, it always grows out and wide, a bit like a shrub. For this reason, you’ll want to keep it somewhere it can spread its arms out. 

Tip: The more light it receives, the bigger this gem will grow. It’s a very fast grower when kept in the right conditions. If you want a smaller more manageable house plant, then placing it in medium, indirect light is the way to go. 

Pruning – Should I Prune This Plant?

If you have a self heading variety, you won’t need to regularly prune your rojo congo, if at all. If you have a climbing specimen, you might want to prune it to keep its shape as it matures. 

With a clean pair of pruning scissors, you’ll want to cut back damaged or diseased stems and leaves.

Repotting

The philodendron rojo congo can tolerate being root bound, but it’s always best practice to move it to a slightly bigger pot as soon as its roots start to curl around the base of the potting mix.

Being root bound means your plant is growing well and needs a little more room to expand. 

Signs your plant needs repotting includes:

  • Roots are starting to show through drainage holes
  • Your plant is root bound
  • Growth is stagnant
  • Roots are shooting through the top of the mix
  • Potting mix isn’t draining as well as it used to

Friendly Tip: If you’ve just bought your plant from a nursery or Etsy seller, it’s likely it needs repotting straight away. Nurseries resell their plants when they’ve reached max growing capacity in that container.

When repotting your philodendron rojo congo, keep these things in mind:

  • Choose a pot that has drainage holes
  • Only select a pot that is 1-2 inches inches bigger than the last (no more).
  • Fill with a high quality, loose, well draining potting mix 

Friendly tip: Don’t worry about prying the old mix from its roots before repotting. Your plant’s roots will expand into the new pot with ease.

How to Propagate your Rojo Congo

Botanists generally grow rojo congo’s via a process known as tissue culture. It’s a highly specialized method that the average home grower or enthusiast won’t have any success with. 

The typical propagation method for climbing philodendrons is to take a stem cutting, because climbing varieties have visible nodes. However, the Philodendron “Rojo Congo” has no visible nodes to take cuttings from, making them difficult to get cuttings from. However, you can cultivate what we call ‘plantelets’ which the rojo congo develops as it matures and air layer them.

Top Tip: For best results, propagate at the beginning or spring or summer to really increase the success rate. This is one of the MOST important factors to get right when propagating this plant.

Helping Plantelets to Grow

  • Search for little platelets at the base of the plant. Plantelets will grow where old leaves have died off.
  • Wait until it has a visible stem and aerial roots emerging. Placing the imperial red in a bright location will help these grow quicker.
  • Air-layer the newly visible stem (see below) to help the aerial roots grow longer and stronger. Air layering typically works in 2-3 weeks.
  • When ready, cut the plantlet off the mother plant and pot it in a well-draining, rich soil mix.
  • Care for your philodendron imperial red as usual.

How to Air Layer your Philodendron

  • Look for the small aerial roots shooting out of the plantelet.
  • Take some wet sphagnum moss, and wrap it around the aerial roots.
  • Using a transparent plastic bag or press and seal food wrap, wrap it fully around the moss covered roots (it should now look like a moss ball covered in plastic). Make sure to not catch any leaves in this wrap.
  • If you used a plastic bag, you’ll need a zip tie to secure it in place. Press and seal food wrap should tape itself up pretty well (I’ve always found it much easier!).
  • Leave the top and bottom of the seal open. New roots like to dive downwards and this helps them do so without bunching up.
  • Thoroughly mist the sphagnum moss through the open top in the plastic bag every day. This stops the moss from compacting and drying up. Don’t let the moss ball dry out.
  • Wait 2-3 weeks for new roots to develop.
  • Carefully remove the plastic wrap and some of the moss around your new roots. Check that the roots look healthy (white is a good sign)
  • Cut the plantelet just below the new roots with clean scissors.
  • Pot the plantelet in a moist, rich organic potting mix (see soil section above)

Toxicity – Is the Philodendron Rojo Congo Toxic?

Yes, the philodendron rojo congo is toxic to small children and pets if eaten, including dogs and cats. Its leaves contain small oxalate crystals which can cause some local swelling in the mouth and gastrointestinal tract.

Help! What’s Wrong with My Plant? – Common Care Problems with the Philodendron Rojo Congo

Dark Patches Appearing on Leaf

Dark patches appearing on leaves can be caused by drastic temperature changes overnight. Philodendrons are not tolerant of cold temperatures and they definitely don’t like frost! Make sure to keep them away from cold, draughty windows too.

Yellowing Leaves

Yellowing leaves can have many causes including too much watering, too little watering, too low temperatures, too high temperatures as well as pests (yikes!). If you’ve just bought your plant or repotted it, it’s possibly a natural reaction to a change in growing conditions. Your plant could simply be adjusting! Common sense and a little observation is usually all that’s needed to work out what is causing those yellow leaves. 

Brown Edges or Leaf Tips

Browning edges or leaf tips are characteristic of a plant that is chronically under watered, or not watered properly. It’s best to give your plant a good soaking less often than give it little amounts of water more frequently. This makes sure the entire mix and not just the top layers of soil are evenly moist.

Leaves are Pale and Losing Signature Coloring

Pale leaves on a normally darker plant can mean the temperature is too low, the light levels are far too high e.g. direct sun for half the day, or your plant is suffering from a nutrient deficiency (magnesium). With newer plant owners, it’s likely light is the main culprit, though it’s best to make sure all bases are covered before changing your plant’s care routine.

Stems are Leggy

Leggy stems are usually caused by a lack of enough bright, indirect light. A plant’s growth is entirely dictated by the amount of light it receives, too little and you’ll see a more wide, open appearance with less foliage. 

Wet, Mushy Patches Appearing on Leaves

Wet mushy patches that look like water soaked lesions are caused by a bacterial infection called erwinia blight disease. Lesions on smaller plants rapidly expand into tan or black areas on leaves within as little as 2 days. You’ll want to isolate the plant from your collection, change the potting mix, prune the damaged leaves and give it as much ventilation (moving air) as possible to let the leaves dry out. Unfortunately, bactericides such as copper sulfate have proven to be ineffective in curing the infection.

Mushy, not Water Soaked Lesions on Leaves

This disease looks very similar to Erwinia blight disease or leaf spot except that the lesions rarely become mushy and do not look water-soaked. You should treat this infection the same way as you would erwinia blight (see above).

FAQ – Commonly Asked Questions About the Rojo Congo

Is the Philodendron Rojo Congo Rare?

Yes! The philodendron rojo congo is considered a rare houseplant. It’s highly sought after by collectors due to its unusual and striking red foliage.

Should I Provide a Pole for my Philodendron?

Provide a pole or stake for your rojo congo and it might take to climbing (and reward you with insanely wide and gorgeous leaves)! Similarly, if placed near a bookshelf, a wall or even a window, this little beauty might try to attach itself. As the stems become thicker and heavier, it’s best practice to pin them up. 

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