Asked April 13, 2021, 12:25 PM EDT
I've attached photos of my fern (kept on my screened in porch in warm weather with southern exposure and kept indoors in colder weather by a southern window), which started experiencing leaf drop this winter with some type of sticky substance covering the leaves. I replanted the plant into a larger pot, thinking that it might have been root bound, which turned out not to be the problem. I also made sure I was watering it frequently/thoroughly enough. That didn't seem to solve the problem either. Then, I started to spray it with Neem every 7 - 14 days. This helps for a while (stickiness and leaf curl and drop ceases), but then the sticky problem returns. Lately, I have to spray it every week. I'm not sure if I'm using the correct product. If so, how long do you think I'll have to keep spraying it? If not, what should I be using? I do not see any bugs/insects on the leaves, and when I use the spray, I completely cover the plant until it drips (which is why the plant is currently outside, now that the weather is warmer). I coat the under and upper sides of all of the leaves, including stems and at the base of the plant where it meets the soil. Please advise.
Baltimore County Maryland