Juttah,
What is the ph of the soil?
It looks orange, test the soil to make sure it isn't too alkaline.
Tea olive like it on the slightly acidic side.
Buy pine mulch for it also, at least 2-3 inches to hold moisture in for it. It likes pine mulch.

I could be just wind and sun damage. In general you tree looks fine to me.

Imidicloprid is like cotton candy to spider mites. Not only that, but you are killing off your beneficial insects along with bad. Guess what bugs will come back with a VENGEANCE once the good ones are gone? You guessed it, the bad ones......That is just 'nature' working side by side with pollution and man's destructive behaviors. It his own demise.

Ever see what happens once the grass in your lawn is killed off with the weeds? You guessed it, the weeds come back.

To me that looks like either thrip damage that is rotting off, or sun burn. I can tell you that mine hates full sun and in fact it was Rhizo who suggested to keep mine in more shade. Worked like a charm:-)

Good luck

Mike:-)

Thank you for the helpful replies!

Something I failed to mention - we used to have a gorgeous 12' tall Willow Acacia just to the left (south) of the Osmanthus, which would've provided much-needed midday shade. Unfortunately two freak cold snaps (14 and 16 degrees) back in February killed just about every Willow Acacia in Tucson. I replaced it with an 8' Netleaf Hackberry, which is thriving, but it'll be a few more years before it gets big enough to shade my poor Osmanthus. I'm going to look for some shade cloth today.

The soil pH is just a hair over 7 according to my el-cheapo soil probe :) You're right though, my plant looks like it's heading towards chlorosis. Very common issue here in the desert.

About the imidicloprid - I hate applying stuff I can't even pronounce, but I was desperate. Last winter, every new leaf on this plant was stunted, puckered, and wrinkled by thrips. So a neighbor gave me a nearly-empty bottle of Dominion to try, and it seems to have done the trick.

Before that I tried tin foil and daily jets of water to no avail. Fortunately I've never seen any insects visiting the Osmanthus flowers, at least not during the daytime. In contrast, our late Willow Acacia was covered in bees and other pollinators whenever it bloomed. (Also - just about every wild honeybee in Tucson is Africanized, so we don't worry too much if we kill a few here and there, hehe.)

What can I try for the thrips - insecticidal soap? I got rid of spider mites on a nearby juniper with rubbing alcohol, would that work? Would better cultural practices help? I'm open to any non-toxic suggestions... thanks again all you helpful people!

The tree looks a bit sparse, but sometimes Osmanthus does that, send out long shoots with few leaves. The stem looks thick to me. You can tell the tree just had a flush of new growth, the new leaves normally start from red-purple, then pale green, then deep dark green.

I put all my container grown Osmanthus in full sun (I am in Zone 5 though), I have two. What I discovered is that more sun, more compact, more flowers. But you do have to watch the watering. You never let them wilt, otherwise, brown tips will follow. They do love slight acid soil, this is a must.

Is Imidicloprid a major ingredient of Bayer Advanced Protect and Feed? I have mixed feelings of this systemic. I know I should go organic, there are so many organic ways. Neem oil is my favorite. But sometimes, you just can't get rid of some pests like Mealy bugs. They could be hiding in the roots, and what I am treating is a precious plant. So I will treat it once with guilt. You know what, mealy is gone. Then I treat them regularly with Neem. Works perfect. Summer sun and wind will rid most of them all by nature.

My experience is like yellowthumb-- I grow mine in full sun, but the leaves brown off seriously if it gets too dry.

The climate here is a lot more humid than Tucson, but I actually water my osmanthus more than twice a week. In my experience they like to be moist. Not wet, of course, but drying off between waterings leads to the brown leaf syndrome.

My guess is new leaves being creamed by too much dryness.