stickstring, I tend to think of light, temperature and moisture in combination. During periods of cooler weather, I increase the interval between watering unless probing (always, for me) the medium indicates otherwise. I tend to be stingy with fertilizer; and apply it as the temperature gets to 70 degrees 'around the clock' in Spring. I would apply more as I detect symptoms of need in the plant (mainly by leaf coloration). I always look for symptoms of positive response about 7 days after fertilizing. If there is none, my work begins.

Full disclosure: the (truly) container plants of which I take care, are indoor and decorative. I do start and grow plants in container-like conditions until they are planted out in the landscape.

I fertilize at every watering all winter long indoors under fluorescent lights with 1/4 tsp/gallon of RO water.

The chlorosis could be related to any of a number of things, so it's hard to offer advice I would consider as meaningful w/o more info.

Al

If I lived in California I would do just as Al recommend...

Nick, have you checked your water pH? You should have very nice green leaves if your pH is lower than 7.0 and if your mix is nice and porous, which is why I have to use vinegar and a 1.1.1 or 5.1.1 mix..I know that Fourwinds has the most green colored trees and they have to acidify their water to do so...

How's your mix holding up? How are the temps at night and by day? What's in your mix? How do you know when to water? What kind of pot is it in? Is it root bound? What zone are you in?

More detail for sure)

Mike

Mix is a 5-2-1 mix, trees have been in the mix for 8 months. Mix looks good. Pots are 15 gal AirPots. No chance for being root bound. They were air layers and roots have a long ways to go before filling pots. I am in zone 8a nor cal. Night temps are dropping to 50-55f at night, averaging 70-75f by day.

I fertilize as Al does.

I back off a little during the deepest three weeks of Winter, then I resume as soon as the sun returns and the plants "wake" a bit. But, truly, I water at least once a week, and so I fertilize once a week. Sure, there is some interior leaf-loss, but quite minimal compared to what I see of other folks posting around the country.

Josh

WHERE DID YOU GET THOSE POTS? I love them!

Mike,

Iam doing great. I hope you are well. Thank you for the kind words. I have learned a lot! I owe the success of these two trees to you, al, John, josh and many more. Very very appreciative. I have used all of the info you all have given me and tried my best to care for these two trees.

Josh,

thank you for your response. My plan was to keep these trees outside all winter. That's why I was concerned about feeding. I left them outside all last winter and they did good. I covered them when a frost was possible.

Mike,

They are called Air Pots.

https://m.youtube.com/watch?v=hsakG5JRUcI

Some people love them, others consider them a waste of money. A friend of mine owns a hydroponics store which caries them. He has been "bragging" about these things since day one. He grows multiple things inside his store and exclusively uses these air pots now. He has shown me root balls of his plants after being in the air pots for a year or more and they were mind blowing. He told me since my air layers had "virgin" root systems that I would be very happy letting them grow and mature in this type of pot versus hard wall pots. After seeing his rootballs I had to do it. So that's how I ended up with them. I am VERY happy with them, all of my citrus are thriving in them. I am very happy.

Ok guys, I just watered and checked my trees and the two branches that seemed to be turning slightly yellow are now black. They died off. Can I remove them now, or do I have to wait until spring?