I don't know if this is the case with your trees, but I've had that happen to a couple of my Meyer lemons when I've been lax about fertilizing. They tend to need fertilizing at about twice the frequency as my other citrus. Maybe your Eureka also needs a bit more food than the other citrus. Also, I've not found the yellow leaves to really green up again, at least not much. Usually what happens when they get to that point is they tend to drop the yellow leaves over time and replace them with new leaves. If I've been good about fertilizing, the new ones will be nice and green. So I think if you keep up the better care, the next flush of leaves should be much greener. This post was edited by BarbJP on Thu, Jun 19, 14 at 13:42

Cece. I'm not sure your lemon has insects..the holes are pretty large for most plant bugs, at least bugs I'm familiar with. What state are you in? And what state was your tree purchased from? I'm in IL, and during summer when citrus go outdoors, flying bugs come fluttering by..every so often, they nibble leaves, but by autumn all signs of insects are gone. The bad thing is they leave holes, the good thing is bugs die in days, and do not linger and kill like plant pests. To be on the safe side, inspect for bugs. Scale, Mealy, Spider Mite, Aphids, Leaf Miner..I'm not sure I covered them all, but those mentioned are insects to worry about. Normally, when insects attack, they leave signs. Yellow and/or sticky leaves, webbing, brown or white bumps, white cottony patches. I notice most rips are on the edges of leaves..Is it possible something is rubbing up against your tree? Human or animal? By the size of the tree, it'd have to be one animal..When a leaf rips it commonly browns. For starters, hose off your lemon..if you have a sprayer, add a 2-4 drops of liquid dish soap. (Not Dawn) But before spraying, check for signs of pests. If you spot any signs of plant insects, you can treat according to bug. As for flowering/fruiting, when a plant is stressed, it sometimes halts production..Actually, until you find out what's causing the problem, lack of fruits might be best. Flowering/fruiting takes energy. Toni

With very little to go on, I'll hazard that a couple things are most likely happening.... First, transplant shock...assuming you've recently re-potted (during the coldest time of the year, no less). Second, lack of nutrients while the roots were "offline" - again, assuming a recent transplant. How long did you wait to fertilize? How much fertilizer did you use? Third, cooler temperatures slow/impair/halt/prevent the uptake of Nitrogen and Calcium, two key elements in maintaining the green color of Citrus. Overall, the tree looks very healthy. Like Al said, I wish all my Citrus looked that nice at this time of the year. Josh

Your tree looks hungry to me. Make sure when you are watering you soak slowly for a long time and wait longer between waterings. Don’t worry about your clay soil, there are plenty of citrus groves here in the Coachella valley planted in clay type soils mainly in the thermal/ Mecca area. These groves produce tons of lemons, grapefruits and oranges with no soil amendments. Unfortunately, this time of year is tough on our trees, my trees also get chlorotic due to the cooler temps and less sun, you’ve compounded the issue by planting your tree in a grass area. Citrus trees are bad competitors for nutrients, the grass will get them before your tree does, so you’ll have to feed it that much more to make sure it’s getting enough npk. What type of fertilizer are you giving your tree? Do you know what root stock your tree is on? I can’t seem to feed my My Eureka tree enough, like my Meyer I usually give it 1.5 times the recommended rate of fertilizer when I feed it. Here’s my tree, in ground for 4 years on Volkameriana root stock. Evan