I am very new to citrus, especially in containers and you can read back some of my posts which prove this. Meyermike has been a god send, as have many others here on this forum.
Please take my advice as a newbie comment, although as I have been tought, it seems as if potting medium and watering may be the culprit. Whenever I notice my leaves begining to curl, I find my potting medium either too wet or too dry. Especially in your high heat.

Like I said, newbie comment... If soil is wet (too wet for too long), possible root rot. I wouldn't check for root rot until one of the citrus "pro's" on this forum suggest to do so.
Just my too cents, hope it helps.

Looks like they desperately need to be watered. It looks like you did water, but perhaps you allowed the trees to dry out too much, and the trees are simply in shock from not enough water. I would move them to a shady area, keep them watered appropriately (not too much, but not bone dry), and allow them to start to recover. One you start to see new leaf flush pushing out at the leaf nodes, fertilize (be sure to water first, fertilize, then water in the fertilizer).

Lastly, be sure you have well draining potting medium. Something out of a bag is going to be too dense. I use 3 parts MiracleGro Vegetable Soil (that particular one, not any other), 1 part perlite, 1 part small bark mix (I use coarse orchid mix or reptile bark from PetsMart). For fertilizer, I use Osmocote Plus (MUST be the "Plus" formulation, as it has the appropriate NPK ratio along with all the micronutrients), as well as using full strength Dyna Gro Foliage Pro once a month.

Patty S.

OMG hugs looks to me the black pots got to hot and damaged the roots. And the tree had enough roots dieing and couldnt take in enough water for the heat. Short version Trees look like they are dieing of thirst. I would paint pots white to keep heat down or Repoted them into light colored pots. Move them into part shade and water and care for carefully. I wouldn't fertilize until I saw signs of new leafs. Hope this helps.
Trace

definitely not enough water. Plants from local retail nursery will be watered once a day and sometimes that is not enough. Especially after carrying them home, when you move the plants, they can break the seal of the soil to the container. When that happens, the water just runs down the side and out the bottom and does not water the plant.
For now, water every day and be sure the water holds in the pot for a couple of minutes and soaks in slowly (not running down the sides). a place with partial shade until it recovers would be best. This is for So Cal, may need less water in other places.

You guys are completely right, as usual! I took the plants out of the pot to see what's going on and the soil was a huge brick of solid dirt, completely dry even though I watered this morning (and I water every morning...)

I got all the soil off the roots and replanted into a 511 mix... Which of course, my golden nugget was already in, hence that one didn't dry up!

Had no idea that soil could get so dry that it won't absorb water.

Guess I won't be getting any citrus this winter... Except for golden nuggets- there are tiny fruits growing :)

I started gardening last year. I used miracle gro for all my pots and tried only one pot of 511 because I wasn't sure if I made it correctly. Now I know to break up the miracle grow w perlite and bark! Makes total sense. I find that 100% miracle gro gets extremely dense and unmanageable after time. I have a huge container full of it and I am going to try to break it apart and mix in some perlite & bark.

Thank you all! Learning so much from you guys.

That's wonderful...If more people like you were not so afraid to look at what;s going on below the soil line, they would know what their trees are dying for, or from)

Glad you figured it out with all these nice people suppporting you.

Mike

My newly planted trees in their new mix :) hopefully they'll be happy now.

Yay glad u figgered it out.
Trace