Check with a lens for spider mites or scale on the underside of the leaf; if you don't find any, it is probably just old leaves; and the tree is sucking back the energy from the leaf to use for new growth/flowers/fruit

Yes, as John notes, those are almost certainly just old leaves that have lived out their lives. A citrus leaf has a life span oh 18 months to 2 years. When an old leaf is no longer capable to preforming all that is required of it , the tree discards it. However, not to waste any nutrient that may still reside in the leaf, it first removes all remaining nutrients for the tree's use. There is no welfare plan for old citrus leaves.

Ok that makes sense. But the leaf in the last pic is new growth. The tip is getting yellowish brownish and sort of crispy looking. What could that be?

Crispy tips may be due to salt build up in which case you could flush the salt out with plenty of water.

Ok well I think that may be from my tap water thats causing the salt buildup. So what I just did right now, since my citruses were fairly dry, was I mixed 4 tablespoons of distilled vinegar into 2 gallons of tap water and also applied 2 teaspoons of foliage pro and then watered my citrus with it. Would adding vinegar to tap water help prevent salt buildup?

Since the tree of concern is a small container tree, and your water is high in soluble salts it would have been much better to have flushed with pure rain water or distilled water from the store.

Ok well would regular drinking water like Poland spring water work? I think distilled is a bit more expensive

Yes

What kind of fertilizer are you using that calls for a half tablespoon per gallon of water?

I agree..Soluble salts in your mix. Looks like you have a very peaty mix there. Like a sponge, it absorbs salts from your fertilizers and tap water. Make sure you are not over fertilizing too.

Sorry I meant 1 tbsp per gallon, not half. I use foliage pro dynagro. Alright well then I will water my citrus with human drinking water from now on... although my wallet will start getting more emptier and emptier.. guess I gotta do this if it means my precious little citrus will live on

I don't know where you live, but the amount of human drinking water (never heard of that phrase before) that would be required to water a small container citrus tree would normally cost so little that it would be considered free.

My Meyer completely defoliated due to salt build up. I water exclusively with rain water now. One day I’ll have a nice collection system, but for now, I keep a bucket under the gutter pipe and then dump that into empty milk or vinegar jugs.

Cory does everything just about the way I do! She is a gem here!!

Hoping you have been well Cory. I wish you were here more often. Finally warmer weather.

Mike

Hi Mike. I am always reading even if I don't always have time to post. There are many others here that share good information fortunately. Got the last of my trees out yesterday. Hard work lifting those 15 and 20 gallon pots! I really can't go bigger than those by myself. The orchids now have the greenhouse back to themselves again. I can now move some of them back to there after spending the winter in my house.

Cory

Fortunately my citrus doesn't seem to mind indoor conditions. They do just fine in my room over the winter. They even flower indoors! But yea for the fertilizing, I can't do it once a week because it takes longer than a week to completely dry out. I let it outside in the rain yesterday after watering it the night before that and I hope it doesn't start stressing out from too much water it received. So far it showed no signs of overwatering. I think I will start buying distilled water then. I would probably only spend like 20$ a year for that to water my citrus. Unless we have a bad drought.

Heruga, It is good you put it out to get the rain water drench. It was a nice gentle but steady rain. My trees leaves look so glossy and green now from being out in it. I hope yours looks better too.

Cory

Early rains have a lot of Nitrogen. Here in Guatemala City, we had our first rain of the rainy season (May to November); it turned out to be a real frog strangler (my definition of 2 or more inches in an hour). Now everything will be green and clean again.

Cory, I don't know how you did it! All by yourself and all your strength. you amaze me and I too have all my orchids still in my greenhouse although I cheat once in a while. I will take all my exposed root orchids growing on bark and spaghnum and stick them in this rain. It feels so good to be able to have much more room for mine! I can't wait to stick them all out in the rain. Wouldn't it be nice to be able to just lift the roofs off our greenhouses?? All the rain they can get without ever having to remove them.

I'm glad you are ok these days. We need our health to be able to do as much as we do. Good nite long time friend.

Mike

Hi Mike, lifting off the top might be easier than moving them all. ; - ) I move them a little at a time to their outdoor spaces and it is not too bad. I can rest between. It is harder bringing them back in the fall when they have doubled in size and I am worrying about an early frost. It's harder to take my time then. The rain really does them good. Cleans and greens them all up. I'm glad to hear your orchids are doing well.

Cory

Watering pots exclusively with distilled or de-ionised water can starve plants from both macro (like Ca and Mg) and micronutrients. Unless you are sure you fertilise with the full spectrum of nutrients, not an easy thing I should say, using distilled water should be done only for flushing the soil every once in a while.

I’m no expert but when my mandarin has yellowing leaves I put a bit of vinegar in the water and boom fixed. Magic.