Lemon Tree Question

I bought a lemon tree, from Lowe's, nothing special, about a year ago. It does OK for me considering my climate. It's indoors most of the year, outside for June-August. I'm just curious because when I bought it, it had no variegation. Now, a bunch of the leaves have this variegation to them. The areas in the picture that are whitish coloured are not dry, the leaves don't die, they just have white patches. Is this a virus or anything. It gets a ton of blooms on it and gets baby lemons but they usually fall off when they are about the size of a walnut. I don't mind, I like the blooms. Just curious about the variegation thing and why it happens or what it is.

Thanks,
CMox

Another pic.

I have a dwarf grapefruit tree with the same problem. It is called Biuret's Toxicity. It's caused by the presence of an impurity, biuret, in urea-based fertilizers especially foliar sprays. I normally use citrus fertilizer, but when I ran out of it, I used what I had on hand about twice.

I know it is progressive. Two summers ago, one small branch on my grapefruit tree showed signs of toxicity. Last summer, a good portion of the tree was affected. The new growth is green, but as the leaves mature, the tips begin to whiten out. This spring, all the leaves were affected. The tree is significantly weaker than it was last year. The last two applications of slow-release citrus fertilizer have done nothing to improve its appearance.

What I can't find out is whether there is a cure or not. I suspect that it's fatal. as none of the things I've tried have worked. I hate to toss it because it produced such great fruit. After the 4th, I'll get our local extension agent to contact the A & M Citrus Center for me. If I get any new information, I will let you know.

It's difficult to get a citrus tree to produce fruit indoors. Even outdoors, citrus will self prune about 95% of its fruit.

http://edis.ifas.ufl.edu/CH142

Wow, great information Bettydee - thanks! I never heard of that. It's odd because I have never sprayed it. I only have ever used some of that dilute "Schultz" houseplant food on it. I guess that must be urea based? It would be great to have additional information. Where do you get your citrus fertilizer? I would like to get some but it's not available locally that I can find. You know, we don't have orange groves in Iowa! LOL! Maybe I can get a small container online. Maybe since it is early in its life, it can improve? It is only about 18 inches tall, but quite bushy.

Thanks again!

Whenever we're in Houston, I go to Southwest Fertilizer to buy it.
http://www.yardgeek.com/

I hope your little lemon tree makes it.