My cute philodendron started getting these spots when it was pretty new from the store. All the original leaves became "spotty" at the same time. New growth is pretty, with large glossy leaves, but it looks like they will also be getting these spots in a few weeks. There's no evidence of bugs. The air roots are thick, and wrap around the base of the plant. It's well-watered, and located in a small bedroom with a large split-leaf monstera, several Jade plants and a couple of schefflera. The plants overlap a bit, but the room gets great sun and warmth from the south-facing window (south coast Oregon), as well as okay circulation. I have looked through loads of photos of spots/discoloration, but nothing really resembles this. Will someone please identify the issue and help me heal my buddy?

A yellow ring with dead tissue inside it in philodendrons usually means a systemic fungal disease. You need to invest in a good systemic fungicide like Phyton. NOT a topical fungicide. You need something that the plant can absorb which will work from the inside out

I'd suggest a systemic copper fungicide . I doubt it's sunburn. Usually there's directions for how much to mix with a gallon of water

I'd also remove the affected foliage and move it away from the other plants if you can.

Phyton 27 is a combined copper fungicide and bactericide. Its not cheap, but it works. You may need to largely defoliate your plant to get all the affected leaves you can see.

You need a systemic because this is moving through the venous system in the plant. A topical won't help

Thank you! Sounds like systemic fungicide is the answer I've been looking for. And sadly, I'll be cutting off loads of leaves. I'm so grateful for all your help!

Almost all fungicides work best when used prophylactically rather than remedially. Tebuconazole is a very good systemic fungicide.

Are you sure there isn't a cultural issue at work here? Have you been fertilizing with regularity; and, are you certain you haven't been chronically over-watering? Have you sprayed the plant(s) with anything within the last month or so?

Al

Take it from someone who has grown philodendrons since the 1980's. This issue is very common with aroids grown inside the house. It can also be quite common in greenhouse environments where it can be a lot more humid and much hotter than the interiorscape of a house. Whatever fungicide you choose, be very careful applying it. It would be best if you could take the plant outside to treat it.

tapla said: Almost all fungicides work best when used prophylactically rather than remedially. Tebuconazole is a very good systemic fungicide.

Are you sure there isn't a cultural issue at work here? Have you been fertilizing with regularity; and, are you certain you haven't been chronically over-watering? Have you sprayed the plant(s) with anything within the last month or so?

Al

I have not sprayed the plant; there's no evidence of any bugs, even through a microscope. I fertilize occasionally only. I water when the soil becomes fairly dry (not shrunken).

Gina1960 said: Take it from someone who has grown philodendrons since the 1980's. This issue is very common with aroids grown inside the house. It can also be quite common in greenhouse environments where it can be a lot more humid and much hotter than the interiorscape of a house. Whatever fungicide you choose, be very careful applying it. It would be best if you could take the plant outside to treat it.

I'm curious about this. The room is fairly small, south-facing, and has pretty good circulation due to strong winds that come through the often open window. I'm on the southern oregon coast; the average summertime high temp is 66 degrees. Would this issue show up in the other plants in the room? I have a large split-leaf monstera (shown in one of the photos) that shows no discoloration. Other plants are shefflera and jade. The plants do touch.

What would the issue be with application of the fungicide? I did purchase the copper treatment, but have not applied yet, nor have I cut off the affected leaves.

Yes fungal disease can spread.
Copper fungicides are generally deemed to be safe for home gardeners. They are known to be eye irritants, and you should avoid breathing them in.
Back in the day, we all (here in Florida anyway, I guess I should not speak for the rest of the country) used systemic product called Funginex. It has since been taken off the market for home use. It was largely used as a fungicide for roses, people here who were trying to grow hybrid roses had to spray religiously once a week in the hot months. But it was also used for other ornamental plants. It was pretty toxic. It was recommended to wear full protective garb including eye protection and a respirator, but of course, no one did right?
It had a sister product, Orthene which is an organophosphate pesticide. And these two were ALSO sold mixed together as a product called Orthonex.
Organophosphate pesticides carry the same warnings as Funginex did.
You can still buy Orthene in the form of generic Acephate. I use it myself, its my go-to pesticide. But you have to be careful.
Copper fungicides are considered much less toxic than the old Funginex used to be, and also less toxic than Organophosphate pesticides. You want to be sure you are not breathing them in, getting a lot of spray on YOU, and I have no idea what they would do to your paint or furniture or carpet. Its best to use them outdoors.

Most people I know that use Phyton 27, Phyton 35 and other systemic fungicides have collections of small plants grown as houseplants in 'cabinets', which is a new popular convention, in indoor greenhouses, or just sitting around in the house in different places. Treating a small plant or localized collection of plants is not too hard. They do spray where they grow, or take them outside and bring them back in if possible

You have a single very large plant. It would be difficult to move, but if it were me, I would move it out to treat it.

Gina1960 said: Yes fungal disease can spread.
Copper fungicides are generally deemed to be safe for home gardeners. They are known to be eye irritants, and you should avoid breathing them in.
Back in the day, we all (here in Florida anyway, I guess I should not speak for the rest of the country) used systemic product called Funginex. It has since been taken off the market for home use. It was largely used as a fungicide for roses, people here who were trying to grow hybrid roses had to spray religiously once a week in the hot months. But it was also used for the ornamental plants. It was pretty toxic. It was recommended to wear full protective garb including eye protection and a respirator, but of course, no one did right?
It had a sister product, Orthene which is an organophosphate pesticide. And these two were ALSO sold mixed together as a product called Orthonex.
Organophosphate pesticides carry the same warnings as Funginex did.
You can still buy Orthene in the form of generic Acephate. I use it myself, its my go-to pesticide. But you have to be careful.
Copper fungicides are considered much less toxic than the old Funginex used to be, and also less toxic than Organophosphate pesticides. You you want to be sure you are not breathing them in, getting a lot of spray on YOU, and I have no idea what they would do to your paint or furniture or carpet. Its best to use them outdoors.

Most people I know that use Phyton 27, Phyton 35 and other systemic fungicides have collections of small plants grown as houseplants in 'cabinets', which is a new popular convention, in indoor greenhouses, or just sitting around in the house in different places. Treating a small plant or localized collection of plants is not too hard. They do spray where they row, or take them outside and bring them back in if possible

You have a single very large plant. It would be difficult to move, but if it were me, I would move it out to treat it.

Thank you! I bought the Phyton 27, and plan to take the plant outside to treat it.

Hi, Everyone! It's so wild that this thread was included in yesterday's newsletter!

I have 5 or 6 indoor philodendrons of different types. And just added a small one last Tuesday, a lovely "Prince of Orange." After reading this entire thread, I looked at all my philodendrons and they all appear to be fine.

Except for the new one!

He has some new growth that's so far perfect, but the older green leaves all have small spots on them. I've attached 3 photos. Do you think the spots are the fungus mentioned in this thread? I bought him at a small local garden center, but I don't know what kind of care regimen he received before that—I haven't had the Prince long enough to have even watered him one time.

Thank you for your help—and this timely newsletter. Thank you, Ruralite, for posting your questions and photos!

The first photo with the pitted spots is old insect damage. They probably found an infestation of thrips or scale and treated it. The second I can't really tell

ImaPlanterNTx said: Hi, Everyone! It's so wild that this thread was included in yesterday's newsletter!

I have 5 or 6 indoor philodendrons of different types. And just added a small one last Tuesday, a lovely "Prince of Orange." After reading this entire thread, I looked at all my philodendrons and they all appear to be fine.

Except for the new one!

He has some new growth that's so far perfect, but the older green leaves all have small spots on them. I've attached 3 photos. Do you think the spots are the fungus mentioned in this thread? I bought him at a small local garden center, but I don't know what kind of care regimen he received before that—I haven't had the Prince long enough to have even watered him one time.

Thank you for your help—and this timely newsletter. Thank you, Ruralite, for posting your questions and photos!

I hope you find answers! Everyone has been so helpful, and I'm fast on the path of making my plan healthy. I was not able to find images that matched my issues, but this group has been amazing! Good luck!