Problems with Indoor Avocado: Yellowing Leaves and Browning Tips
I grew 2 avocado plants from the pit, and they've been growing well for quite some time. They are now about 2 ft tall. A few weeks ago, I noticed some slight yellowing on the leaves and browning at the leaf tips. I checked the roots and noticed that they were pretty root bound and needed repotting, so I repotted them. But the yellowing and browning has gotten worse. Here is a picture of how it looks now. http://www.flickr.com/photos/17398687@N02/5301425262/
As you can see in the bottom right picture, I have the plants under fluorescent light in the daytime. Also I've noticed that new leaf growth is turning white, drying, and falls off to the touch (Upper left picture). I thought maybe the yellowing could be N deficiency, so I fertilized with a houseplant fertilizer and this hasn't seemed to help, so I'm thinking maybe chlorosis? How can I treat chlorosis in a potted houseplant? I don't really want to fertilize again with it being wintertime. And I still don't know why the leaf tips are browning? I have also noticed that the lower leaves (which are very large) are very stiff and drooping. Is this from inadequate light? Because the fluorescent lights don't really reach the lower leaves well. Do you think the fluorescent lights are too intense on the upper leaves? Desperately need advice on this ??