Well established orange and mandarin next to each other. This year they are really struggling even though they have had mulch added for the first time in years. Loss of leaves is obvious. I have a wild passion fruit that has sprung up nearby. Should I get rid of this?
I Have Struggling Citrus Trees
How deep was the mulch? More than 3-4 inches can smother a plant. Did you put mulch around the trunk?
The following statement came from the article listed below: "Never pile the soil or mulch up against the stem or it will get collar rot, which is extremely common in citrus trees."