Hello,
I purchased this plant (unknown name) at a nursery in the eastern Ontario.
Although there were already black spot on some leaves, I was expecting that new leaves would be growing fine.
But every new leaf comes out with black spots…
Are they sick? what can I do?
Thank you for contacting Toronto Master Gardeners
The plant in the photo looks like either variegated German Ivy, (Senecio mikanioides) or, a variegated pathos (Epipremnum aureum) plant. I believe it’s likely a pathos because of the stem and opposite leaves, and described black spot on the leaves.
The cause of spotty leaves for a pathos, and other plants, is a bacteria Pseudomonas cichorii, or bacterial leaf spot that affects young leaves. This infection can be exacerbated by humid weather fluctuations, poor moisture drainage or too little light for the plant. Make sure your planter has proper drainage, and is not sitting in water. When watering the planter, take care not to splash the leaves of the pathos. P. cichorii loves wet humid weather, more so with this summer’s current heat and moisture. The pathos will need good air circulation to stop the bacteria from multiplying.
Removal of the infected plant is a last resort.
The University of Florida provides information on several leaf diseases including Pseudomonas chichorii: Leaf Spot Disease