Depends on what it is they need. Maybe try sampling and testing soil near them, seeing if a particular nutrient stands out as being in short supply.

It does seem possible it's a nitrogen deficiency due to that nutrient becoming less available during cold weather. If you planted with intact potting soil rootballs the potting soil could be all leached out, the roots not having grown out into the surrounding soil far enough yet to make up for this.

NSCU Cooperative Extension should be able to help with soil testing.

Mine look exactly like yours, huisman...they got nipped by our 8oF night not too long ago, and the leaves are dying. They'll flush out with new growth soon and return to green status. Bboy's suggestion of soil testing is very valid, though, if you haven't done that yet. But osmanthus aren't terribly picky about soil and nutrients in general.

I did wonder if it might be cold damage. Not used to dropping of burnt leaves being preceded by them turning yellow, however. Maybe it's because the same chilling that affected the top made nitrogen pretty hard for the plant to get out of the extra cold soil.

If I were checking this out in person I'd want to pull one of them up and look at the roots and soil. As the roots go, so goes the top.

Nitrogen deficiencies are usually indicated by chlorosis of the older (lower) leaves since N is mobile within a plant. This plant appears to be severely chlorotic at the top. And remember, extension soil labs don't test for N.

I'd wait before doing anything, though. My tea olive, which has been in the ground for 3 years, suffered some cold damage this winter, too. The upper leaves are now just starting to yellow just a bit. I'm hoping that it's not a sign that the entire root system was damaged.

Plant looks pretty bad off. Nothing to be gained by waiting - once problem is identified.

Here is a link that might be useful: NCSU Soil Testing pdf

I am having the same problem here in Durham, NC too. I have four tea olive plants at different locations and they are showing the same symptoms --- yellowing and falling leaves. One of mine has actually been with me for the last 8 years. The rest were planted last year. I wonder if the drought 2 years ago, then the cold this past winter shocked the trees. I will appreciate any info to address this problem. I am quite attached to my osmanthus. THank you.

My tea olive are doing much better now that the weahter is warming up. I spoke to the nursery where I bought my plants last year and they said the yellowing was probably a result of the colder than usual winter we had. Sure enough it looks like they were right. I did go ahead and give my plants a treatment of Espoma Hollytone organic fertilizer for good measure. They are nice and green now and have lots of new growth!

Here is my Tea olive plant today. Looks much better!

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