Yeah, a bit is the answer you’re looking for.
Too rootbound and you’ll struggle to get enough water or nutrients into them, but if they’re in too big of a pot then you’re running the risk of it getting root rot.
Do Philodendrons need big pots?
I tend to plant all my plants in a pot that’s a bit bigger than the root ball.
It can be tempting to just buy the biggest pot you can afford and just have to repot your Philodendron once, but there are a couple of reasons this isn’t a good idea.
- If you have a lot of soil in comparison to roots, then the soil will stay wet for ages, and the oxygen levels in the soil will deplete (soil roots can’t absorb oxygen from water very efficiently). Low oxygen levels can cause anaerobic bacteria to multiply like mad and that’s where root rot comes from.
- Some aroids like to be a bit rootbound, and if they’re not, they make it their mission to fill the soil with roots. All other growth will halt until they’re feeling cosy in their pot. This isn’t a problem in itself, but it’s a bit annoying when you’re like ‘it’s so sunny and you’re fed, watered, and humidified (?) but you’re not freaking growing.
Philodendrons need big pots if they have a big root ball. If they don’t they don’t!
How to know when to repot your Philodendron
The first sign that your Philodendron *might* need repotting is roots coming out of the bottom.
HOWEVER
If you read this article on repotting Monstera (and Monstera and Philodendron are related – second cousins, shall we say?) you’ll see that my Monstera had a LOT of roots protruding from the bottom of the bottom of the pot, but there weren’t actually that many IN the pot.
This happens because roots tends to grow down, especially if you bottom water, but also because gravity dictates that water flows down, so even if you top water, the bottom of the soil stays wetter for longer (for reasons other than just gravity, but the fact is that soils grow towards the water, and water usually ends up at the bottom of the pot).
Don’t repot in this situation. You can either leave it be, or take the plant out of the pot and repot it in the same pot (with the same soil) but with the roots in the pot.
I leave it quite late to repot. If I can still see soil on the rootball, it can stay where it is.
There are a few signs that your Philodendron might be ready for a repot:
- It’s thirsty all the time
- It’s looking a bit yellow (from nutrient deficiency)
- Roots are growing out of the top of the soil
When you go to repot, only go up a size or two BUT the bigger and more established the Philodendron, the bigger pot size increase it can handle.
Do Philodendrons like to dry out or be moist?
No Philodendrons like wet soil, so all will need to dry out to some degree – I would usually water at around 2 or 3 on the moisture meter.
However, there are three different types of Philodendron when it comes to growth pattern:
- Climbing
- Crawling
- Self-heading
(There are also some hybrids that are semi-climbing, but they’re just climbers that are crap at holding on and need additional support. Philodendron pink princess, I’m talking to you)
Anyway
Climbing plants like to dry out a bit more than crawling and self-heading types, so they like to be a bit more potbound than the crawling types.
Crawling types tend to have bigger root systems though, because their stem (actually called a stolon) creeps along the ground and every new node develops its own roots.
Crawling types are best planted in long pots to allow them to crawl properly, but because they like moister soil, they don’t mind having more soil than is strictly necessary in the pot.
In short, don’t worry about having to have a small crawler in a pot that has a lot of soil volume, because they typically have a lot of roots and like damp soil.
Mother, I blame you
I have an article on which Philodendron crawl and which ones climb here.
What happens if you don’t repot a rootbound Philodendron?
Over time the soil will get pushed out as the roots displace it.
I always think of soil being yeeted over the side of the pot when I write about roots displacing soil, but I think the soil just gets so compacted it starts to breakdown and runs out of the drainage holes.
The actual roots being potbound aren’t an issue. They get all tangled up but they’ll still function and they won’t strangle the plant (at least, I’ve never seen evidence of that happening).
The problem is that we need soil to hold water and nutrients for our plants to live in.
You can keep plants without soil. I have a bare root orchid because I can never keep them alive so I went right back to keeping it as close to how they grow in the wild (though there are no Kilner jars in the wild – that’s to keep humidity at the roots) as I can.
All you have to do to keep a soulless plant healthy is regularly soak it in nutrient water. Which is fine for some people, but a ballache for others.
I wouldn’t keep a Philodendron bareroot, so as soon as they start needing watering every few days, I repot. The thing about Phalaenopsis is the roots are green when they’re hydrated, so I just soak it whenever the leaves stop being green. Philodendrons roots don’t have a handy colour-change function, so into soil they go.
Once your Philodendron is super potbound, you’ll need to water it every few days, which is too much for some people. If you’re happy to do that, go ahead.
There will come a point when the plants will fill the pot with roots. Some plants will happily burst through and break the pot, most will escape through the drainage holes. If there’s no room for more roots, the plant will dramatically slow down its growth, because it needs to balance its growth and the volume of roots it has.
It will take longer for climbing Philodendrons to reach this point than crawling or self-heading ones.
Climbing philodendrons are hemi-epiphytes, so they develop an aerial root system that can absorb moisture and nutrients (though not particularly effectively) from the air.
If you have your climbing Philodendron trained up a moss pole, the aerial roots can grow into the damp moss and get moisture that way.
If you have a decent moss pole that you maintain properly, your plant can keep on growing despite being rootbound (plus climbing Philodendrons will start concentrating more on developing the adventitious roots any roots that aren’t underground ones – rather than subterranean ones).
Crawling and self-heading Philodendrons don’t have aerial roots, so once they’re rootbound, they’ll need repotting.
Since crawling Philodendrons roots every node on the stolon, this may happen faster than with a self-heading one BUT since they need bigger pots anyway, it’s not really an issue.
What size pot should I put a rootbound Philodendron in?
Don’t go too big because you’ll freak it out. I would go for one that’s an inch or two bigger all the way around.
When it comes to repotting root bound plants, I recommend being gentle. Don’t tease the roots apart or anything – just plop the plant from one pot to another and pack damp soil around the edge.
Leave it to acclimate for a couple of months. The roots should start to grow into the new medium but if they don’t, sitting constantly next to damp soil will have softened them up a bit. I rarely break rootballs up, but if you prefer to, I’d wait until this point to do so. The roots will be less brittle and therefore you’re less likely to get snappage.
Final thoughts
Most Philodendrons like to be snug in their pots, but crawling and self-heading Philodendrons usually live in damper conditions in the wild so are less tolerant of being left to dry out. If they are rootbound, ensure you’re regularly soaking them in fertiliser water so they get enough moisture and nutrients.
