What’s wrong with my mango tree

Question

I have watered it, just trimmed all the really bad ones off, but it still has black on edges of leaves. What can I do?

Answer 1

From what I see at a first glance is TOO much water. Not the correct formulation of fertilizer and/or improper pH. I am hoping this soil is potting soil from a bag? Your plants, all plants need us humans to add a balanced fertilizer. Fertilizer never comes with soil of any kind unless they ADDED fertilizer to the soil. Then you have to know what that is before adding any fertilizer.

Please tell us what kind of soil, is this environment out on a shaded porch/patio? Very good.

Black edges means (normally) high salts in the soil (tap water)? I am seeing deficiency in phosphorus and nitrogen. What have you added for fertilizer? Do you know how to test for pH?

Feel the heft of this pot and plant and soil after you've watered. That pot and plant and soil will feel incredibly lighter when you need to water again.

Fertilizer is a huge deal for plants we humans want and need to grow. "Less is Best, More is Death and None is Dumb". What is the plant just to the right of this plant in the picture? Another mango? It also looks a bit anemic.