I see leaves like this occasionally on my garden Meyers; it is usually caused by plants that are producing fruit and growing at the same time and likely not getting enough nutrients. What happens is the plant literally sucks the life out of the older leaves and puts it into the fruit and new growth; if your new growth has good color, then that is likely what's happening. I don't see this symptom in my field trees; but the garden trees have to compete with grass, flowers, etc. and citrus are not good competitors; for inground citrus it is best to clear all grass, etc. under the tree to the dripline. For container plants it is easier to deal with. I would suggest you look for Vigoro citrus/avocado food and apply according to the label; it is what I use for my garden citrus, but it's a bit pricey for field use. Fish emulsion is really not a very good fertilizer for citrus; and your soil incorporated slow release fert just may not be keeping up with the growth and fruits.

They are in pots;-)

First off I have to say that the garden center does not know what they are talking about. I have yet to see one nursery owner in my area that has any experience growing a citrus in a container.
They won't because they will not respond to the care their other plants get, therefore, too much work. Besides, most of the people I know that work at garden centers are not educated enough with citrus, not even gardenia or any unusual tropical plant not use to growing in these parts..

In fact, most that come here learn more at one sitting than any one that sells them...Ok, now that that is off my chest.lol

Relying on Fish Emulsion is a no and will only make matters worst..Well, what do we know?LOL

I will be back:-0)

I agree with these guys on the Fish Emulsion.

When you say nice fresh potting soil, what do you mean? What sort of mix are you using?

Josh

http://edis.ifas.ufl.edu/ch142

might be nitrogen deficiency, doesnt look anything like the other types.

maybe a pic of the actual tree would help. also most slow release only lasts 2-3 months. how long ago did you use it?

Here is the thing.

Many can make a diagnosis and some can be dead on in fact. But what is more crucial to me is 'what the cause is" and then to address that.

Only you can determine what you are doing wrong or try and bring and much detail to the table here about your cultural practices, elements the tree is subjected to, what it is planted in and ect.

It's a good start that we know they are in pots, you live up north, and that you may be fertilizing incorrectly

Mike

Listen to Josh and Mike they know what they're talking about. The slow release won't help short term and may not be enough(or indeed too much) long term.

When I had a similar problem (and take my advice with caution as I'm new) I used an ammonium sulphate solution (preferably weak) watered in with each watering until they greened up.

It could be your original compost mix had some nutrients in which have now completely depleted, baring some pest or stress factor.

Regards
Nick

Pictures of the entire plants will be much more helpful than individual leaves.

But if all the leaves are that color --extremely yellow -- the trees are in serious trouble.

Thank you all for your input and advice. And sorry for the suspense - I couldn't find the camera cord.

And another apology - I said "soil", but should've said "mix": I've got them growing in metro-mix 830 (peat, composted bark, perlite, vermiculite, dolomite lime, and blue chip).

Below are links to the pics of the trees as they live in their environment. I posted links rather than the pics themselves so that I could keep the images large enough to show as much detail as possible.

Houstontexas123 thanks for that link. After comparing mine I would say it looks like their iron-deficient leaves look most like mine, but again, when it comes down to it, I can't say that any of them look anything like mine.

After reading your generous comments above, and reading the back of the metro-mix bag (where it recommends a constant application of fertilizer after at most the third watering), and contemplating my own ignorance, I'm pretty much coming to the conclusion that my poor citrus are deficient in probably pretty much just about everything. Heh.

I guess what took me so long to wake up was that it took me so long to hit bottom. My Meyer is six or seven years old now, and has been producing happily and abundantly in the same pot until only last year without aid of any more than a general granulated house plant fertilizer that I put in the water when I brought them in for the winter.

{{gwi:635159}}: you can see the newer growth is even yellower than the old growth (you should be able to enlarge the images by clicking them if they don't automatically fill your brower).

{{gwi:635160}}: older growth is yellowing out and dropping off. You can see a few fruit, also sadly yellowish.

{{gwi:635161}}: newer growth yellower than old as well.

I looked around the internet and town good and long for Vigoro citrus and avocado fertilizer but couldn't seem to find anyone who was selling it or could order it, so I picked up a box of Dr. Earth's Fruit Tree Fertilizer. It lists citrus as a primary use, so ought to address my flagrant nutrientlessness. It's quick-release too, so hopefully I'll see some results soon.

should be ok, as long as it contains micro nutrients.

Organic isn't recommended for container culture, given the lack of consistent soil microbe populations.
I'd pick up something else, and save the Dr. Earth for the raised beds or the garden. That's where the
"organics" work best.

Josh

Coco:

I am glad you finally took steps to correct your situation.

May I ask, did you add perlite to that mix? It looks like it is well draining.

How old is it? Do you use tap water or rain water?

I am curious. What is your fertilizer plan? Will you be using full strength? How often do you think you will do it? Does that fertilizer contain Ca, Mg, and S?

I use a fertilizer by Dyna-Gro called Foliage-Pro 9-3-6. It is a 3:1:2 ratio which plants like and has ALL the primary macro-nutrients, secondary macro-nutrients (Ca, Mg, S) and all the micro-nutrients. It does very well for me.

Also a good check of your water supply to see what kind of pH it has will do you wonders. Mine is 8.5 and that is exactly the color that many of mine would change to over months of watering with a pH that high.
Some plants including citrus that prefer lower pH levels also have difficulties absorbing Fe, Mn, Cu, or Zn, which is more tightly held in alkaline soils, another reason why they thrive in lower pH watering solutions.

Mike

More great questions/advice.

I've been watering from a well (unsoftened) for the last four months. Before that, tap water. The problem definitely started more than four months ago, but I can't rule out that it hasn't been exacerbated by the new water source. I'll definitely test the pH ASAP.

I haven't added anything to the growing mix. Just straight out of the bag. Re: age - I didn't touch the soil at the roots' core when I potted up, but I did loosen the periphery and shake out the old soil there. I'm totally ignorant about root pruning so I don't know if that was something I should have done at the time (feel free to leave that one for another day).

When I bought the Dr. Earth's the guy at the store mentioned that they (dr. earth's) were "all about the soil," but I didn't pay it much mind because I didn't think it was relevant. So, so, so much to learn... :)

I was planning on using Dr. earth's at maximum strength per instructions (haven't read them yet) and then playing it by ear, but I'm going to try to find the Dyna-Pro now, with which I will most likely do the same.

I don't have a fertilizer plan beyond that. Any recommendations that a behind-the-curve horticulturist like me needs to hear?

One more variable I ought to mention: Last winter I put these trees under a 1000W Metal Halide Light and let the room get too hot, and too dry, and definitely stressed them out. I would guess that they have yet to fully recover.

thanks again,

steve

Hi Steve.

Sometimes it can take months for citrus to recover from stress, and for some it can take merely a few weeks, depending on your cultural habits and the conditions provided for them.

As long as your soil is porous and the roots are fine, your tree should make a full recovery and rather quickly in the coloration department.
You can help this along by providing the right mix, right temps, right pH, right light, right ferilizer, and getting to know their needs and them on an individual basis.
This will come with time.

Checking your pH is a great idea.

If it were me, I would of cut wedges out from the rootball and a 1/3 from the bottom so the roots could grow into the new mix. I have also been known to bareroot a many. That is when you remove as much as the older mix as possible to allow the roots to occupy the new mix in no time.

Foliage Pro is wonderful and I hope you get access to it some day.

As for the other fertilizer, I have never used it. I just hope it doesn't clog up vital air spaces within the mix with time or encourage compaction.
How much you use, fertilizer that is, and how often would depend on the type mix you use.

Ask anytime, that is what we are all here for.

Mike