It's possible that with all the rain, a lot of the fertilizer has been flushed out or you have problems with the roots and you should check them. I would use a slow release fertilizer like Jobes Citrus & Fruit or Epsoma Citrus Tone and let the rain wash it in if the rain continues. I think it's low on nitrogen. I would also add Osmocote Plus for minerals that the citrus fertilizers mentioned lack. I also use fish emulsion 1x a month. I figure with all three items fed to the trees, I have all the bases covered. lol.

The yellow vein leaves are older leaves that are being dropped; the plant has taken back what nutrients it can and when the whole center vein is yellow they will drop, or you can just pick the off. I wiould give the plant more food; and not over water it; and you should see some new growth soon.

Well, there you are John! Thought you left this earth. I am happy to see you.

John, thank you. I just took some more photos. Denise told me above what her feeding schedule is with her Meyer lemon trees. I will upload what I just took a few minutes ago. I continue to spray with with Neem oil, water and a few squirts of dawn as well.

Denise- I can check the roots tomorrow by putting the pot on its side and emptying it. What should I be looking for?

The yellow leaves are just old leaves being shed by the tree. A citrus leaf has a life span of 18 to 24 months. One word of caution....Other than water, spraying neem or spraying any type of spray in an assumed hope to kill some phantom problem is not a wise thing to do. Only spray when a problem actually occurs.

Thank you for the information, Jodi. I wanted to tell you that the underside of leaves and some of the stems still had scale on them as of two weeks ago. I thought that you had to keep spraying for future generations of scale that would crop up. This tree has been battling scale for 4-5 years in some form or another.

A lot of people use neem for battling pests, but there are times when you need to bring out the big guns. Battling scale for 4-5 years is way too long when there is an alternative available. It's not organic, literally stinks and kills insects on contact. Many folks don't like it because it will kill beneficial insects, but if there are beneficials on when you spray with neem, they are going to die as well. Anyway, I use malathion because it kills scale on contact while neem take 24-48 hours. I worry about neem oil blocking the stomata (pores) in the leaves and the leaves dropping off if it's used too often. Think about your own skin and what oil does. I may be over thinking it. lol. You can spray malathion any time during the day as well so that is a big plus in my eyes.

Old leaves do drop during the blooming season, so don't panic when it happens. My patio is covered with old leaves right now. What a pain. lol.

When checking the roots, you are looking for root rot. They will be dark brown and mushy.

Thanks everyone, for your answers. I have another question. The citrus fertilizer I have is Sunniland Brand Citrus & Mango fertilizer 6-4-6. It doesn't look like it is organic- ingredients are sulfur, coated urea, phosphate, activated sewage sludge- yuk, copper oxide, potash, borate etc etc. Instructions on bag say one cup for 1 year old plants- 3' high. I have had my plant for maybe 8 years and I is only 3 feet high. A struggling plant for sure! I don't want to give it too much fertilizer- this sound like a lot for such a small tree. Then how much of the osmocote plus should I apply- would it be just scattered on surface of the soil? The fish emulsion I can figure out. I just want to get this plant happy and growing. The last time I had a good crop of lemons was maybe 5 years ago.

Does your product label say how much for container plants? The amount it recommends for a 3 ft tree sounds about right for in ground trees; but it seems like it is way too much for a container tree. If you are growing in containers, always make sure your products have recommendations for containers. Too many products are simply re-packaged from larger amounts without any research about using them for container plants.

Do you live in the States? I use Epsoma Citrus Tone or Jobes Organic Citrus & Fruit Tree. No spikes. For the age you have given of your tree, it should be bigger. I use Osmocote Plus and use about a level capfull or maybe a bit less. If you have already given citrus fertilizer to your tree, wait 30 days and try a different brand. If you are unsure on the amount to be given for any fertilizer, contact the manufacturer. I did that with Epsoma and Jobes as I don't trust my math. lol. Keep in mind that the organic fertilizers need heat to break down, so don't use them during the cooler months when inside unless actively growing. I gave some late September or October last year and it just formed a yellow layer on top of the soil so use a liquid fertilizer while inside. Oh yeah the organics stuff does have an odor which dogs really like so scratch it in too. lol.

Thanks all. I checked the package of Citrus fertilizer and it doesn't give potted plant amounts. I will buy some Osmocote plus and try to find some organic fertilizer.

Why organic fertilizers? Plants do not know the difference except in order for my trees to utilize the right amount of nutrients in the right ratio, my trees need the perfect microbes to break it down which almost never happens in pots. Therefore the reason many complain of nutrient deficiencies when using organic fertilizers

Much more reliable are chemical fertilizers for my tree such as suggested above.

I too use Omocote

When I have seen that yellowing pattern so consistently through a tree with leaf drop it has always been root rot, cold and wet roots, or a combination. I had that exact problem with a Meyer in a fabric pot when I first got into citrus. I think the tree is reclaiming nutrients from leaves and shedding them because the roots are not providing enough nutrients.

PacNorWreck, I repotted the tree last week, because I didn't like the look of the soil mix it was in. I remixed it with more perlite and some fine pine bark mulch. (I hope the pine bark mulch is alright) So far, no new leaves. The roots did look fine though, when I repotted it. I just want to see the tree grow. It does have old issues though. The trunk had a part that looks funny to me, but it has been this way for years. It is not a strong robust tree for a while now. Wish I could get it going real good!

If you re-potted into a pot just a little bigger, you could get new growth in a cupla weeks; if you re-potted into a notably larger pot, you might not see growth for 2 months... Be patient and keep giving it TLC.