I've had this plant for a month or so and it's clearly unhappy, the leaves have been quickly turning yellow and brown before falling off. The nursery we got it from said it sounded like it was over-watered but we have been watering it pretty carefully (around once per week). Other people we've asked have also suggested overwatering as the likely cause.

I've checked the roots and they seem fine, the soil is not soggy – if anything it's fairly dry throughout.

Much of the advice we been given seems specifically focused on Monstera and Philodendron and I'm wondering if perhaps this plant has slightly different needs? I haven't noticed any reduction in leaf loss after watering or inbetween watering. Also it is still growing new leaves. I can't help but wonder if it's actually under-watered but am nervous to water more given the advice I've recieved.

Anyone have any experience?

Yes it does look fairly unhappy. It looks like it was pretty rootbound. Repot it into a larger container with fresh soil. I wouldn;t wash the roots or anything drastic, just plop that root ball int a new home. You can just snip the yellow leaves off.
The care between the different aroids is largely based on whether a plant is terrestrial or epiphytic. The Monsteras, Rhaphidophoras like tetrasperma and decursiva, the Epipremnums, and the climbing Philodendrons are mainly classed as hemi-epiphytic, meaning that they can start in soil but then become climbing epiphytes with adventitious roots. They can also start out of soil, rooted in crevices of rocks or trees in leaf litter and be epiphytic from there. Or, they can start rooted in soil, and later decide to sever that connection and grow as pure epiphytes. Many Anthuriums can also grow as epiphytes.
For your purpose, you should treat your plant as a hemi-epiphyte/terrestrial. It will need to be sized up in pot size occasionally as it becomes root bound so that it can uptake water more efficiently.

Thanks for the info, very interesting!

I was wondering if it should be repotted when I pulled it out yesterday, so I will do that.

Regarding watering do you have a recommendation? As everyone was suggesting it was over watered we let the soil dry out a fair bit between each water but I'm wondering if it's just been too dry the whole time. Humidity is quite low here at this time of year (<30% often) and despite having humidifiers running quite a lot, I expect it also dries out quite fast.

My moisture meter shows it to be pretty dry right to the centre, 5 or 6 days after the last water.

Its really hard for me to advise you on watering. Because I don't grow any of my aroids as houseplants. I grow both outdoors in the ground and in a greenhouse, so I water with a hose. What state do you live in? Whatever your humidity is outside, it is even lower in the house...both AC and heat dry the air even more than just the ambient outdoor humidity. Is it possible to grow the plant outdoors for part of the year?

I'm actually in Southern Ontario (Zone 5a ish), but yes it certainly can go outside in the summer, lots of my plants do and thrive. The humidity and temps are generally high.

I think after repotting I'll try to increase the moisture level in the soil for while and see if that improves things.

Well, over the past 40 years I have read all the data that gets preached to people about growing Monsteras and other like aroids as houseplants, and have to say, I disagree with most of it. Lighting is a biggie....everyone says shady...these can and do thrive in full sun. Water...they say don;t overwater....but I water DAILY with a hose and have no problems in the greenhouse, where some plants are actually planted in the ground and some are containerized. Humidity can be a deal breaker though, for these as it can for many many plants. I think you just have to kind of experiment and find what works best in our special set of conditions, no one else's set thing that works for them will work for everyone 100% of the time

Thank you so much that's great to know – I appreciate your thoughts and knowledge. I will be repotting today and we'll see how it does.

Gina is truly the aroid expert but I think I might try and loosen the root ball because you say it is dry in the middle. Often when plants are rootbound that potting medium in the middle is so dry it is hydrophobic, rock hard and difficult to re-moisten. You don't have to be too drastic, just break up the root ball enough to break up that dry mass so water can penetrate it. You could even just poke a few holes in the root ball with a skewer.

true!

Thanks Alice, we'd already repotted before seeing your message so we'll wait and see what happens now I guess. We potted into a high quality soil mix in a terracotta pot and have been watering carefully to try and get the whole thing evenly moist.

It's probably too early to tell but it feels like the yellowing has slowed already so

How is it now?
I take all my plants outside for summer so they get refreshed in humid air and SHADE, natural light, longer days, before another winter indoors. I even think natural rain is good for most plants.
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