On Saturday (6/20/2020), I received a 3ft Cogshall mango tree in the mail from Florida. I quickly repotted it in a 10 gallon pot with potting mix. I left the pot in my yard, where it gets plenty of sun here on the Gulf Coast of Texas (zone 9a). The tree looked healthy upon arrival and it looked fine until two days ago.

On Monday, we had heavy rain for hours and hours, so my poor tree got soaked. Since its pot had drainage holes, I didn't think it mattered. However, on Tuesday, I noticed that some of the leaves on the lower part of the stem were turning yellow. A few of them fell off. Yesterday, I noticed that all of the lower leaves on the stem were yellowing, most of which fell off. I began looking into this, and realized that my tree's roots were drowning in the oversized pot. So I repotted it in a 7 gallon pot and added quite a bit of perlite to the potting mix to improve drainage and air circulation.

The good news: I have not see any new yellow leaves on my tree today (some of them have a bit of yellowing on the underside). However, I noticed that the leaf tips are black/brown. I looked into this and it looks like it could be tipburn. Mango tipburn is caused by moisture deficiency, salt accumulation or extreme fluctuations in soil moisture. My guess is that repotting it from a soggy 10 gallon pot to a smaller pot with better aeration caused the tipburn but I would like to hear from others. I'm hesitant to flush the pot today since the roots were drowning up until yesterday, but I'm happy to flush it tomorrow. Any advice would be appreciated.

Pictures are included.