In my experience citrus like a lot of sun. If I put them in a spot that gets shaded by another tree, I have to constantly prune that tree in a way that the citrus gets at least 6 hours of full sun a day. I've removed a few shading trees due to this and the citrus perked up a lot by the next year. It looks like it might be the case with this tree, but it's hard to tell from the picture.

Another thing with citrus, make sure the ground is drying down to at least 2 inches deep before you water again. This fully depends on the soil type but in the case of clay, it's about that much. And citrus seem to prefer clay, so that's the ideal composition provided there aren't *too* many rocks. This drying out takes longer when you use mulch, so make sure you check the ground to know the watering schedule it needs.

I took the picture pretty early, so it does get more sun than shown, but it's true it gets shaded by the other trees for a few hours. The watering though...it looked decent (but not great) up until it got really hot in June. During the heat I figured I wasn't watering enough. Now, the soil is moist, but it still looks pretty limp every morning. Miss a day and it's really wilted. I'm wondering if I'm overwatering now, maybe all that clay is saturated.

Citrus are one of the more sensitive plants to being over watered. They don't like to sit in wet soil all the time. The roots will start rotting and the plant won't be able to take up as much water from the soil. You'll see drooping leaves when this happens, which usually prompts people to start watering more, which causes more fungus to grow, rotting more roots.. and so on.

One way to fix it is to prune the foliage back some more, and let the top few inches of soil dry out to kill off some of the fungus. If all the leaves remain on a tree that has fewer roots than it used to, the whole thing can die if it can't keep any part of it hydrated. You'll know you pruned off enough when the remaining leaves perk up again after a day or so.

Sometimes you'll see whole branches die but other branches are fine.. this is fairly normal when a plant loses a whole root section. It's also another reason you don't want to cut off whole branches when you prune to fix this issue, but rather cut the remaining branches in half or more, then cut off the dead ones in a few weeks when it stabilizes.

"You cannot over water in Phoenix unless you have a irrigation problem and the soil is downright soggy."

I guess the "unless you have an irrigation problem" could mean anything? If it doesn't, I don't know who told you that, but that's wrong. Most of the areas in Phoenix I've been to have clay soil and that is easy to over water in. Clay loves to retain water and anything that has any kind of sensitivity to root rot will die pretty fast if it doesn't dry out occasionally.

If that statement was referring to container gardening, that's one place I would agree. It's almost impossible to over water in the summer time in containers, although that depends on the soil type in the container.

And btw, what nutrient deficiency causes leaves to stay green, but droop on a citrus?

Landy I've learned the hard way. By starving my 40+ citrus in clay after reading overwatering hype like yours. Citrus trees are tropical and demand food and water. Lots of it. The OP appears to not be supplying enough hydration. And once you stress the citrus I have found that it can take a full year to reinvigorate growth. Lets get more facts. I stand by my comments.

Oh, water deficiency causes leaf droop. I suggest rereading the op. "Perks up a bit"

We do need to know that.. OP, how long are you watering when you water? If it's hours, that's proper watering for clay soil. If it's only a few minutes then that could be the problem your tree is having.

Also, Molewacker, where are your 40+ citrus trees located at? The difference in soil type really makes a difference when it comes to watering them.

It now has 5 2gph drippers on it that come on twice a week for 1 hour in the early morning. On those mornings it looks a little happier when I get up. Since it looks wilty on non-auto-water mornings, I've been filling the basin once...I estimate the basin is about 6ft across, and when water starts spilling out it's 2 to 3 inches deep (hard to tell with the mulch). When it flowered, I hammered in about 5 of the citrus fertilizer spikes. I fertilized again with a loose citrus fertilizer in August, just scratched it into the mulch.

I should probably mention we are on a well. Running the water means running the well pump, and my husband is getting a little nervous about the age of the pump, so he has minor anxiety about running it for hours at a time.

The tree doesn't look like it's dying...no leaves are dropping off, I don't see brown edges on any leaves...but the leaves are narrow and lighter green than my other (much smaller, and not wilted) citrus tree. And usually curled up and wilted.

More data...I dug a 10" deep hole just outside the basin (as far as I could go with my soil knife). The clay soil at the bottom is powdery and slightly moist. I can form a ball in my hand but it breaks with any movement. The auto watering came on this morning; so I think I can assume it is not overwatered?

wilting only in the morning and does it perk up as the day progresses? Could it possibly be overwatered? the fertilizer that you used- is it a high nitrogen fertilizer? Could it be a case of root burn? I recently killed young citrus plants by accidentally using too strong fertilizers. the leaves drooped and yet remained green for a while and became gradually lighter - before the plant finally died off.

:I tend to agree that some gardeners blame overwatering too often. Plants and trees in the wild don't generally "die" during rainy winters, so to suggest that plants are so picky re: excess irrigation that they'll DIE is overstated in my opinion.

Furthermore, it's a GOOD idea to periodically overwater here to flush out all of the salts from our crappy irrigation water here (and water rates are lower in winter--another reason to periodically "flood" your yard in the winter here.)

I'm starting to wonder this myself. I had blamed my peach trees dying on over watering but when I think about it, only the peach trees died that I gave a bunch of water to. In fact, other trees were fine just a few feet away from the peach tree that died. I now have a 1.5 year old peach tree that seems promising *crosses fingers*.

In any case, OP, how's your tree doing now? Did it eventually come out of its slump?

You are watering too little and too often ...

Instead of 10 gallons twice a week, you need to slowly soak it with 50 gallons or so twice a month.

If running the well pump makes you nervous, fill some big barrels or trashcans and use them as a source for a slow trickle into the basin.

It's March 2018; the tree is slowly declining. After the weather cooled, it doesn't wilt during the day anymore. It is not dropping a lot of leaves, but it doesn't replace any that are lost. The color of the leaves that are there is getting lighter...it looks a little like iron deficiency, so I might try some iron fertilizer. And I will switch to the trashcan trick for watering. I bought one of those little pH/moisture meters; I don't know how accurate they are but this one says pH is around 7.

Updating this just for info. Mid-May now. The tree went into serious decline in April; I figured it was a goner. I was watering using a 30-gal trashcan with a 1/4" drip tubing trickling in water every couple weeks as suggested above. So irritating when it lost 2/3 of the remaining leaves and the smaller branches died. I got out a shovel, pickaxe, and the rock bar and managed to dig down 18" - the soil was dry. So I've trickled water on it almost continuously for 3 weeks now, filling up my trash can twice a day, and I'm now seeing tiny leaf buds on many branches. Time will tell if it just wasn't getting water and will re-grow, or if this is its dying gasp. It's sure planted in some hard dirt; it's not caliche but cement-like clay and rocks.

DG,,,, Leaf growth... that is great news! Excellent detective digging work. Now, its patience and more patience.

As you know, once some soils dry out, they can become annoyingly hydrophobic. My soils are that way and a slow or drip application is the most effective way to rehydrate. Also in my case a fast application will only drain down through mole tunnels.

Good luck and please do continue to update... that is how we learn........ pictures?