In this post I would like to introduce you to the plant genus that gained a lot of publicity lately – philodendrons. If you follow Kaylee Ellen’s vlog, you are perfectly aware that we can find a philodendron (and not only one) on every level of the “rarity scale”. The Philodendron spiritus-sancti is now the Holy Grail in the mind of every plant collector with his over the roof prices (the highest price that I saw, was 6000 USD, sic!). Pricey and rare now, because there are only six (!) known specimens left in the wild due to rainforest devastation.
With almost five hundred described species, it the second-largest genus in the Araceae family (colloquially known as aroids). Let’s face it – almost everyone has a philodendron, even if they don’t know it. Why are they so popular? First of all, there are a lot of species in this genus which are easy to care for, even though they originally come from South American rainforest. Secondly, their foliage variety is simply stunning – from small heart-shaped ones, trough the spear-shape, to huge, undulated, twice the size of your head, as well as pinnated ones. You can get a tree and you can get a trailing space-saving beauty. Don’t get me started on their colour variety, there is something for everyone: for baroque or minimalist interiors. The choice is yours. Most philodendrons are also easy to propagate, which makes them available for mass production.
I want to show you my small collection and guide you through basic plant care. I will take into account some of the nursing nuances and my personal experience.
Ideal potting mix for philodendrons
There are different levels of mastery here. Factors affecting the type of substrate that we are going to use are your patience (yes!), the fussiness of the plant and the effect that you are tying to achieve. What we are looking for in our ideal mix:
- pH – 4.5 – 6.0 (fairly acidic then)
- good aeration
- adequate water retention
- warm soil
The most common philodendron mix that you find in hip plant books and on basic plant-care sites (and that The Aroid Society does not approve of, believe me), is as follows (you have to take one part of each medium and mix it together):
- universal potting soil
- peat moss
You are allow to use it. I mean, most of the common philodendrons will survive in it, some of them may even like it, because plants are able to develop some tolerance to their environment. Some of the species are also already used to European houses, because they have been on the market for a long time. By now they look differently than the original species and rarely do they achieve the shape and size of the adult plant in the wild. In good conditions they develop to their middle form. Try to use this mix for common Philodendrons like: scandens, selloum, xanadu, erubescens, mandaianum, micans.
What we want though are big, lush leaves and plants that are strong and grow quickly. If you were to visit a rain forest you would quickly notice a few things about the soil that philodendrons grow in. It is composed of leaf litter, decaying wood, compost, animal droppings and the charcoal left behind from forest fires. Remember, most philodendrons don’t grow in the ground, but are attached to other trees. There are actually not so many terrestrial plants in this genus. Rather than using rich, soggy soil and watering only once a week, I prefer to use soil that holds moisture well but drains quickly.
The optimal mix for philodendrons (“tropical mix”):
- 30% soil
- 20% peat moss
- 40% orchid bark with charcoal
- 10% perlite and/or sphagnum moss
- hardwood/aquarium charcoal/volcanic rock (optional)
If you want to hang your philodendron in a basket, then feel free to use orchid mix for the potting. They can also grow in hydroponics. As Philodendrons are often epiphytes and hemiepiphytes, they don’t really need soil to grow. Knowledgeable growers can even grow them on a stone (sic!).
Positioning your plant
Now we will consider the next important parameter, light. In any rain forest, plants fight for their position and large ones often deprive small specimens of nearly all light! That is the reason why the Philodendron, as well as other species, resorted to climbing trees – they try to reach the light.
As they grow high on the side of a tree, they morph into what appears to be a different species! This new morphed “form” is just the adult leaf shape, different than found on the juvenile plant. And if you want to cultivate your plant into the adult form, you should think about giving them more light. Philodendrons rarely like direct sunlight – some will even survive even in a dark bathroom. What they do want is relatively strong, indirect light similar to that found right at the edge of a forest. If you notice that your plant is getting leggy, you should know that this is not only a sign of insufficient light – it may even mean not enough light for the young form of the plant, which means that you are basically torturing it.
Does it really matter?
As a rain forest species, Philodendrons often experience rain on a daily basis, particularly during the rainy season. And that can last even for six months! So you can’t water them rarely. And if you keep them in a plastic container with heavy soil, then yes, if you water them often, they will rot, but that only means, that you keep your Philodendron in a bad medium/bad pot, not that you have a “heavy hand” with water and you should make longer pauses between waterings. In such conditions your plant is literally getting strangled and the roots will start to rot very fast.
Roots in Philodendron species are designed to collect rain water in the course of the entire wet season. They do suffer in the dry season (but it doesn’t mean that you should stop watering in winter!). I mean…they don’t even normally grow in the soil, and they do pick up a lot of moisture from the dewy fog that they live in. Remember: even in the dry season a Philodendron can collect enough water from the humidity around their exposed roots to survive. They cannot accomplish the same at humidity levels of temperate climates. If you don’t want to water often, you should think about growing them in sphagnum moss, which keeps the moisture in the roots for longer, but at the same time, it doesn’t sodden them and deprive of oxygen.
Since we got to the topic of oxygen, I must point out that all of the soil needs to remain evenly damp to enable the roots of the plant to draw in fresh oxygen. And yes, a plant produce oxygen in its leaves, but it takes fresh oxygen for the roots’ metabolism, so the soil has to have access to the roots. When we have a hard shell on the surface, the soil can’t absorb fresh oxygen, because the water just flows through gaps but does not soak the soil.
Can it be cold tap water? I think that you know the answer already. “Lukewarm” means something different to everyone, so I will only say that you should keep the roots warm. And you have to ask yourself what is the quality of your tap water. Do you have a built-in filter? Then totally go for it. A lot of calcium? It will increase the pH of your soil over time, and as I’ve said – we need to keep the pH pretty low for a medium.
Temperature and humidity
Why cold mist is a plant killer
All Philodendrons are tropical plants, so they can’t tolerate cold temperatures for extended periods. Even air-conditioned environment can be deadly for them. Generally, we should make sure that the temperature does not drop below 13C (55 degrees F). It is best to keep them below 33C (90 degrees F). Since they grow best when in 26-30C, you can often keep them outdoors during summertime in Europe.
Humidity is extremely important! Do everything possible to keep the humidity high around your Philodendrons. You know… the jungle has a humidity level near 100%! Air circulation is equally important since the air is almost always moving in the rain forest. If you can’t give the plant rain forest humidity there is an alternative – fill the pan and gravel with water and then sit your plant and pot on top of the gravel bath in to create a micro-climate around the Philodendron. Water will evaporate around the leaves and make plant believe that it is living in a more humid area. You can also use a humidifier.
Misting? I would say – more “fogging” with small, warm droplets, using rainwater or decalcinated one. If you can’t provide this, it is better not to mist philodendrons, because it might cause ugly spots on the leaves. Also, do not mist the velvety species, like Philodendron micans. They have microhumidity, and warm temperature should create a warm foggy environment. Remember to avoid cold humidity, because it will damage your plants and cause necrosis on the leaves. It is as if you were to try to put one of those naked cat species in Siberia. Not a good idea.
It is a given that, as a plant grower, you carefully clean around your plants, not allowing dead material to sit in the soil, but by keeping the plant pristine you are depriving it of a natural source of fertiliser. Philodendrons collect falling dead vegetation that decays around their roots and provides nourishment. The epiphytic forms even form in a specific way, so the ants can build nests on them and provide constant flow of the organic material.
So, do not over-clean your plants, and fertilise with a rule : “weakly, weekly”. What does it mean? Use 10-20% of the manufacturers’ suggested level and give it frequently to the plant. This way your soil is more stable, keeping stable pH by buffering better, and the nutrients are available for the roots at all times.
How to succeed every time
Climbing philodendrons are easy to propagate from stem cuttings that contain at least one node (preferably two) placed in a glass of water or directly in the soil (if you keep it moist at all times).
Self-heading philodendrons sometimes send out offshoots that can be potted up once they gain some size.
“Making seeds happen'” is in the home environment rather a dream, but if you want to entertain yourself with a movie about it, here is the link:
Prevent and fight to the last leaf
Ah, the “favourite” topic. Pests give sleepless nights to growers all over the world. In Europe, Philodendrons can get pretty much everything on their leaves. In my opinion, thrips are the worst. But most problems that you will face with Philodendron sp. is caused by bad handling of water. It is either humidity, or the watering itself. So I will always advise to watch this very carefully and also to give them a SPA shower once a month (if they are not too big to go under one!).
Those would be the basic care tips, but this is not the last article about Philodendron sp.! I hope that now you have a general idea on how to grow those beautiful plants. Leave a comment, ask me anything, and share if you like it. Thank you for reading!
- R. Berent, Ł. Marcinkowski, O roślinach, published by Full Real, Warszawa, 2017;
- V. Peerless, How not to kill your houseplant, published by Penguin Random House, London UK, 2017;
- www.exoticrainforest.com ;
- Philodendron World Checklist of Selected Plant Families. Royal Botanic Gardens, Kew. Retrieved 2015-09-13.